I had something like this at one of my favorite restaurants and decided to make a variation of it at home. Everybody really enjoyed it. I hope you do too. For extra spice add spicy garlic and/or red pepper flakes.
Toss cauliflower, olive oil, garlic, salt, pepper, and red pepper flakes together in a bowl until evenly coated; spread onto a baking sheet.
Bake in the preheated oven for 15 minutes. Stir cauliflower mixture and continue baking until tender, 10 to 15 more minutes.
Grease a separate baking sheet. Spread pizza dough onto prepared baking sheet.
Bake pizza crust for 5 minutes. Top crust with cauliflower mixture, mozzarella cheese, Parmesan cheese, prosciutto slices, and red pepper flakes. Bake until crust is lightly browned and cheeses are melted, 8 to 10 more minutes.