Preheat the oven to 425˚ F. Toss the potatoes in oil, salt and pepper. Spread on a baking sheet lined with parchment paper or foil. Roast for 20 minutes, or until tender. The blade of a knife should be able to easily puncture the potatoes.
I frequently have a stash of cooked lentils in the refrigerator, but they're so easy, and quick, to make. If your lentils aren't already cooked, go here for detailed instructions on cooking lentil beans.
Combine the roasted potatoes, 3/4 cup of cooked lentils (or more, if you prefer), the minced chives, and chopped red onion together in a large bowl.
Whisk together all of the dressing ingredients in a small bowl. This makes more dressing than you will need, so reserve the rest to re-dress leftovers the next day. Lightly toss.
For the Omnivores
Fire up the grill, nice and hot. You should be able to hold your hand two inches above the grill for five seconds. Lightly oil a grill pan suitable for grilling fish or vegetables. I like to use peanut oil for its high smoke temperature rather than olive oil.
Bring the salmon to room temperature, rub a little oil on it, and sprinkle generously with salt and pepper. Place the salmon, flesh side down on the grill pan, skin side up. Grill for 5 minutes. Flip, add the dill to the top of the fish, and cook another five minutes or more, depending on how well cooked you like your fish. My instructions are for grilling one inch thick salmon medium-rare.
Divide the Vegetarian Lentil Potato Salad into two portions. One portion should be 1/3 of the total for the omnivores, the other portion is obviously 2/3, enough for the vegetarians at the table. Flake the salmon in large chunks and toss into the omnivore portion.