If your sun-dried tomatoes are packed in oil, drain them. If not, place them in a heat-safe bowl and pour boiling water over top to cover. Let sit 5 minutes, then drain.
In a food processor, combine sun-dried tomatoes, basil, walnuts, Parmesan, garlic and about ¼ of the oil.
Pulse a few times to combine everything. With the food processor running, stream in remaining olive oil to desired consistency (you'll want it really oily for a pasta topping, less oily for a pizza topping, etc).
Season with salt in pepper.
Recipe by Flying on Jess Fuel at https://www.jessfuel.com/sun-dried-tomato-pesto/