Shrimp Scampi Flatbread

Name: Shrimp Scampi Flatbread
Ingredients: 2 1/2 tbsp. extra-virgin olive oil, divided; 2 tbsp. butter; 3 cloves garlic, minced; Pinch crushed red pepper flakes, plus more for garnish; 1 1/2 lb. large shrimp, peeled and deveined; kosher salt; Freshly ground black pepper; Juice and zest of 1 lemon; 1 large store-bought flatbread; 2 c. shredded mozzarella; Chopped fresh parsley, for garnish