Spicy Veggie Pizza in Potato Crust

Ingredients

• 1 bag frozen hash brown potatoes (30 ounces)
• 2 large eggs, lightly beaten
• 1 cup grated Parmesan cheese
• 1/2 cup tomato sauce
• 1/2 teaspoon Sriracha hot sauce, or more to taste
• 1/4 teaspoon sea salt
• 1 1/2 cups shredded mozzarella cheese
• 1/2 red onion, sliced into thin rings
• 1 green bell pepper, cored and sliced into thin rings
• 1 cup fresh spinach leaves
• 2 cups shredded cheddar cheese, divided use
• 2 cups shredded mozzarella cheese, divided use