Lightly salt tomato slices and spread over a double layer of paper towels to dry.
Poke pie crust with a fork. Sprinkle 1/4 cup mozzarella cheese on the bottom and bake for 10 minutes until lightly browned. Cool completely.
Combine 1/4 cup cheddar cheese and 1/4 cup mozzarella cheese in a small bowl.
Sprinkle tomato slices with garlic powder, oregano and black pepper to taste. Layer 1/2 of the tomato slices, 1/2 of the cheese mixture and 1/2 of the basil. Repeat layers. Top with halved grape tomatoes.
In a small bowl combine remaining 1/4 cup cheddar cheese, 1/2 cup mozzarella cheese and 1/4 cup mayonnaise. Dot over grape tomato mixture.
Reduce heat to 350 degrees and bake uncovered for 30-35 minutes. Cool before serving.
Note: This pie can be served warm, room temperature or cold.