Melt one tablespoon of butter in a large skillet. Season shrimp with the Tex Mex seasoning. Add shrimp to skillet and saute for about 3 to 5 minutes just until shrimp is cooked.
Remove shrimp from skillet and set aside. In the same skillet add remaining tablespoon of butter and add onions and peppers to it. Saute onions and peppers until onion is translucent then add frozen corn and cook for a 3 more minutes.
Assemble the quesadillas by layering mozzarella cheese, shrimp, then veggies and then more mozzarella cheese on a tortilla and top with another tortilla. Grill quesadilla until cheese melts.