Preheat oven to 400° F. Line a baking sheet with parchment paper. Coat with cooking spray. Set aside.

Place riced cauliflower in a large microwave-safe bowl; cook in the microwave oven for 5 minutes, remove and stir, then cook again for another 5 minutes.

Carefully place cooled cauliflower on cheesecloth and wring out all extra liquid into another bowl. Discard liquid.

Combine cauliflower, oatmeal, egg whites, Parmesan cheese, parsley, and garlic powder in a large bowl; mix well until thoroughly combined.

Form cauliflower mixture into 2 balls, 1 cup each, and place on prepared pan. Flatten gently with hands to form a circular crust. Bake for 20 to 25 minutes, or until crust is firm and golden.

When crusts are done, divide cottage cheese equally between crusts. Then distribute arugula, mushrooms, and tomatoes evenly on top between two pizza crusts.

Raise oven to 500° F, or turn on the top broiler to high. Bake for an additional 5 minutes, or until mushrooms and tomatoes are blistered.

Divide sliced eggs evenly between pizzas. Serve immediately.