Spinach and Sausage Calzone

Ingredients

• 1 pound Pizza dough (store bought)
• semolina flour or corn meal, for dusting
• 1 pound Fresh spinach leaves, roughly chopped
• 3 cloves garlic, peeled and minced
• 1/2 cup diced onion
• 4 tablespoons olive oil
• 1/2 cup grated Parmesan cheese
• 3 ounces garlic and herb soft cheese (Boursin or similar)
• 1 pound Italian sausage (loose or removed from casings)
• Kosher salt
• Freshly ground black pepper
• red pepper flakes, to taste (optional)
• 8 ounces mozzarella, shredded
• 4 ounces Gruyere cheese, shredded
• 1 egg
• Marinara sauce (homemade or store bought)