In a mixing bowl, toss cauliflower, garlic, and olive oil together. Spread on a cookie sheet and bake at 400 degrees for 25 minutes. Remove from oven and set aside.
Place crust in pizza pan and spread Alfredo sauce evenly over crust. Add arugula, roasted cauliflower, shrimp and feta evenly over sauce.
Bake at 425 degrees for 8 - 10 minutes or until edges of crust are brown and toppings are heated through. Allow pizza to rest 5 minutes before slicing and serving.