Add the spinach to a food processor. Pulse until finely chopped. Add in the avocado, olive oil, seasonings, Greek yogurt, and stock. Puree until smooth.
Bring a large pot of salted water to a boil and then add noodles. Cook noodles according to packaging instructions. Drain pasta and set off to the side to slightly cool in the colander.
Add the cooked noodles back to the pot they were cooked in, add the sauce to the pot, and then mix until evenly coated. Serve warm.