Cook the pasta according to packet directions, drain and allow to cool.
Add chopped olives, tomatoes, red onion, feta, and spinach.
To make the dressing; in a food processor or using a stick blender, process egg yolks, vinegar, mustard, and garlic.
With the motor running, drizzle in the oil very slowly until the mayonnaise is thick.
Mix the dressing into the pasta salad.
