This vegetarian tetrazzini is loaded with cauliflower and poblano peppers in place of the traditional chicken or turkey, and switches out the sour cream and heavy cream with yogurt.
Vegetable tetrazzini like this one is great with cauliflower, broccoli, or even butternut squash.
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One of my grandchildren's favorite dinners is chicken tetrazzini. It's the tetrazzini their dad grew up with, and he now he makes it for them. And I agree, it's really good. But since I'm crazy for cauliflower (the one white food we should all be eating lots of), I wanted to make a vegetarian version. I hope you enjoy it.
It's a perfect comfort dinner to make ahead and warm up at the end of a busy day, or make it for Sunday suppers. It's guaranteed to please everyone at the table!
You don't need much more than a salad and crusty garlic bread to round out the meal, but I have more side dish suggestions below.
If you want a more traditional pasta casserole, check out this one-pan meatball casserole.
❤️ Why you'll love this recipe
- Pasta casseroles are crowd pleasers of any age.
- Great comfort food vegetarian main dish that can be served as a side dish for the meat eaters at the table.
- Make ahead and warm up when you're ready to serve it.
- Uses ingredients you probably have on hand.
- Very flexible to adjust for your own taste preferences.
- Great way to get kids to eat more veggies!
🧅 Ingredients + Notes
- Cauliflower
- Poblano peppers
- Yellow onion
- Spaghetti noodles
- Milk - either 2% or whole milk is fine.
- Greek yogurt - whole fat.
- Vegetable broth
- Garlic
- Unsalted butter
- All-purpose flour
- Panko breadcrumbs - or make Panko gremolata breadcrumbs with the Panko breadcrumbs.
- Parmesan cheese
- Herbs and spices
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🔪 Recommended Equipment
📝 Instructions Overview
Detailed instructions for making this cauliflower tetrazzini casserole are in the recipe card below, but here's an overview!
Step 1
Roast the veggies. Cut the cauliflower into bite-size pieces, and roast. Roast the poblano peppers whole. When roasted, peel, stem and seed the peppers. Dice the peppers.
Step 2
Sauté. Sauté the onions and garlic over medium heat until the onions are softened.
Step 3
Cook the pasta. Break the pasta noodles into thirds, and cook just until al dente.
Step 4
Make a roux. In a heavy bottomed pot, large enough to accommodate the entire casserole, melt the butter and whisk in the flour until thickened. Whisk in the milk until you have a thick sauce. Whisk in the broth.
Step 5
Add everything else. Remove from the heat and stir in the yogurt and sautéed onion and garlic. Stir in the cauliflower, peppers and pasta. Once the veggies and pasta are coated with the sauce, pile it all into a baking dish. Top with breadcrumbs and Parmesan cheese.
You can use either a Panko crumb topping dotted with butter, or make these gremolata bread crumbs.
Step 6
Bake. Bake until bubbly.
⏰ Tips to Simplify and Save Time
- Purchase cauliflower already cut up. If your market carries it, these bags will be in the produce department.
- Roast the cauliflower and poblano peppers ahead of time.
- Assemble the entire casserole ahead of time, except for the breadcrumb topping. Cover with plastic, and keep in the refrigerator for up to 2 days. Bring it back to room temperature before baking. Add the breadcrumbs and Parmesan just before baking.
- Cook the casserole ahead, cover and refrigerate for up to 3 - 4 days. Or store in an air-tight, freezer safe container and freeze for up to 6 months.
👩🍳 Preparation Tips
A roux is common in French cuisine as a thickening agent for sauces, and is often seen in Cajan recipes as well. At its most basic, a roux is equal parts of flour and fat (either butter or oil) cooked over low to medium heat until the flour is lightly browned. A liquid is then whisked in, over heat, until thickened.
The liquid can be milk, cream or broth, depending on how the roux will be used. For a gravy, drippings of meats are added.
Check out this recipe that uses a roux on how to get a silk roux sauce.
💡Ideas for Possible Variations
If you don't want a spicy tetrazzini, eliminate the poblano peppers. Cauliflower is a little bland, so I recommend adding a spice such as curry powder.
Broccoli works well in this recipe instead of cauliflower, and in the autumn, try it with butternut squash.
Any pasta works in this recipe, so feel free to use a different type of noodle. For example, this Cauliflower Curried Mac and Cheese uses penne.
Use evaporated milk or one of these substitutes for evaporated milk for a richer sauce.
🍽 Side Dish Ideas
A big green salad with avocado.
Fresh corn on the cob.
If some people at the table like spicy, and other don't, and you omit the poblano peppers, you can serve these Charred Shishito Peppers on the side.
Freshly baked bread is always a hit. If you're interested in making a yeasted bread, these Parmesan and Garlic Rolls are irresistible, as is this Aglio e Olio Pizza Bread. Or stay with a Mexican theme with tomalito, a sweet cornbread.
Quick sautéed baby spinach.
📇 More Casseroles You Might Like
Butternut Squash Casserole with Apples
Broccoli Cheddar Casserole (or Tart!)
Creamy Feta and Asparagus Casserole
Healthy Mexican Casserole with Quinoa
Curried Cauliflower Mac and Cheese
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Cauliflower Tetrazzini with Poblano Peppers
Equipment
- 9" X 13" baking dish
- baking sheet
- Large pot (for cooking the pasta)
- fine mesh strainer
- box grater
Ingredients
- 4 cups chopped cauliflower (about 1 head)
- 2 tablespoons extra virgin olive oil divided
- 1 teaspoon kosher salt divided
- 1 - 2 poblano peppers (depending on how much heat you prefer)
- ½ pound uncooked spaghetti noodles
- 1 cup diced yellow onion
- 1 tablespoon garlic paste or minced garlic
- 4 tablespoons unsalted butter divided
- 2 tablespoons all-purpose flour
- ¾ cup milk
- ½ cup vegetable broth
- ¾ cup plain yogurt
- 1 tablespoon Gourmet Garden Italian Herbs Paste or 4 teaspoons chopped fresh oregano, or 2 teaspoons dried oregano
- ¼ cup Panko breadcrumbs
- 1 cup grated Parmesan cheese
Instructions
- Preheat oven to 400˚F and butter a 9" X 13" baking dish. Line a baking sheet with parchment paper.
- Cut the head of cauliflower into bite sized pieces (I separate out the florets and halve or quarter them depending on their size). Toss in 1 tablespoon olive oil and ½ teaspoon salt. Arrange on the baking sheet along with the poblano peppers, and roast until the cauliflower pieces are tender, and the peppers are blistered and charred, about 20 minutes.Turn the peppers after 10 minutes.
- Bring a large pot of salted water to a boil over high heat. Break the spaghetti pasta into thirds (around 3” long) and cook according to the directions on the box. Drain.
- Sauté the onion in 1 tablespoon of oil over medium-high heat until softened. Add the garlic.
- In a heavy bottomed large enough to hold the entire casserole, melt 3 tablespoons of the butter. When the butter is melted and sizzling, whisk in the flour to form a loose paste. Cook for 3 - 4 minutes to cook the flour.Gradually whisk in the milk. Bring to a simmer, while continuing to whisk, until a sauce forms. Whisk in the broth while the sauce continues to thicken. Remove from the heat, and whisk in the yogurt, herbs, onion and garlic. Stir in the cauliflower, peppers and pasta, being sure to coat everything in the sauce.
- Pour into the prepared baking dish.
- Toss the breadcrumbs and cheese together and spread over the casserole. Dot with the remaining tablespoon of butter.
- Lower the oven temperature to 350˚F, and bake for 25 minutes, or until bubbly.Serve warm.
Stacy Rushton
Creamy cheesy pasta is the best, Susan, and I love your addition of the cauliflower and peppers!
Tammi @Momma's Meals
I love tetrazzini anything! I love love love how you've made this a nice healthy and hearty dish! Happy New Year to you and your family.
TerriSue
Susan, This one sounds fantastic. I went shopping yesterday and decided not to get the cauliflower. I guess I'll have to wait until next week. It will definitely be on my list next week though. I have to try this one out!
Anita at Hungry Couple
Serious yum. I'm basically obsessed with cauliflower. Pinned!
The Wimpy Vegetarian
Me too, Anita! I love, love, love cauliflower!!
cheri
Hi Susan, once again you have outdone yourself, love this recipe. Happy New Year!!
Liz
I wouldn't miss the chicken one bit! What a great vegetarian tetrazzini!
Sarah | Curious Cuisiniere
I love the vegetarian spin on tetrazzini. Can't wait to try it!
Lauren @ Sew You Think You Can Cook
Sounds super flavorful!
Wendy Klik
This is going on the To Try for a meatless Monday meal for sure!!
Rita Held
Yes, cauliflower has lots of possibilities. I often make simple mashed cauliflower rather than mashed potatoes. The only difference is the garlic I add while cooking the cauliflower. And yes, Greek yogurt rather than sour cream.
Serena | Serena Bakes Simply From Scratch
Such a gorgeous comfort food dish! Love the cauliflower! I'm going to try this one of these days for Meatless Monday!
Sarah Reid
AMAZING! Love the veggie twist on a classic, I'm sold as soon as cauliflower doesn't cost the same as a car payment!
Christie
Love the addition of poblanos too!
Rosemary Mark
This recipe is YUMMY! My carnevorous maxiumus man said 'this is good!' on the first bite, by the third bite it was 'this is REALLY good!". We had the leftovers last night after a late-night movie and it was even better!
(I had quite a few re-reads on the recipe --- like the peppers mention roasted in the instructions, and also to roast with the cauliflower; the leeks say diced, but strips in the instructions. I can adapt and it looks almost exactly like yours, minus the great photography and styling. I'll email photos to you 🙂
Monica
I adore this! Cauliflower pastas are my favorite :). This is my kind of comfort food.
Lynne @ MyGourmetConnection
This is a great meatless dish - cauliflower beats turkey in my book!
Betsy @ Desserts Required
I am with you on this one. The chicken may be good here but I would LOVE this dish sans poultry. FAB!!!
Lauren Gaskill | Making Life Sweet
My gramma made this for us all the time growing up! I really like your version too! I never thought of adding poblano peppers! Great idea. 🙂
Christie
Oh my, Susan. This looks fantastic!! I'm definitely adding it to our #meatfree options.
LydiaF
Love the creamy sauce with the poblano peppers. Sounds wonderful with the cauliflower.
Denimo
Susan, I've pinned so many of your recipes, I thought I'd better go ahead and subscribe so I wouldn't miss anything in the future. Really enjoy your blog.
The Wimpy Vegetarian
Thank you so much Denimo!! That makes me so happy 🙂
Shelly
This was a home run!!! Thank you!!! I feel like I get into a vegetarian rut with my Mexican and eggplant parm norms and this is so different from those 🙂
I found it much easier to save dishes and time by:
-Broiling poblanos (takes 3-4 min) separately directly on rack; then could peel white cauliflower roasting
-not roasting the leeks; instead I sautéed them til soft in the large pot then added fresh garlic, then the flour to coat for a rue. Then the wet ingredients and cheese for the sauce and then the veggies and spaghetti.
Can't wait to try more of your recipes! 🙂
The Wimpy Vegetarian
I'm so so happy you liked it so much!!!! Thanks so much for letting me know, and I love your tips for saving time and dishes!!
Margot
Hi
I cannot find the herb paste for this dish. What can I substitute?
Thanks for your help
The Wimpy Vegetarian
For the Garlic Paste, finely minced garlic of the same amount is fine. The bought version just saves times, that’s all. For the Italian Paste, substitute 2 teaspoons of dried herbs. A combination of oregano and basil are good ones to go with. If you opt for fresh, I recommend 4 teaspoons minced herbs of basil, thyme, and oregano. Hope that helps!