Throw everything EXCEPT the olive oil into a blender, or the bowl of the food processor fitted with a metal blade. Add the olive oil and buzz it a few times to completely emulsify.
Feel free to adjust for the oil - vinegar balance you prefer by dipping a salad leaf into the dressing to taste it. Don't judge it by only tasting the dressing. It's always best to try it with whatever it will be served on.
If you don't have pear vinegar, you can substitute apple cider vinegar. The pear vinegar I like is B.R. Cohn's Pear Chardonnay Vinegar, from Napa - Sonoma wine country.
I've used both Bartlett and Bosc pears to make this vinaigrette with great success. Do not use an Asian pear - they're too hard for this recipe.