1. Preheat oven to 450°.
2. To prepare crust, weigh or lightly spoon flour into dry measuring cups; level with a knife. Combine flour and next 4 ingredients (through pepper) in a food processor; pulse 3 times or until combined. Combine oil and 3 tablespoons ice water in a small bowl. With processor on, slowly add oil mixture through food chute, and process until dough is crumbly. Sprinkle dough into a 9-inch glass or ceramic pie plate coated with cooking spray. Press dough into an even layer in bottom and up sides of dish. Bake at 450° for 10 minutes. Remove from oven.
3. Combine ricotta, egg, garlic, and 1/2 teaspoon salt, stirring with a whisk. Add 1/4 cup basil and 1/4 cup Gruyère cheese, stirring to combine. Spread ricotta mixture evenly over crust. Arrange tomato slices in a circular pattern over ricotta mixture, slightly overlapping. Sprinkle tomatoes with remaining 2 tablespoons Gruyère cheese. Bake at 450° for 25 minutes or until filling is set. Let stand 10 minutes. Sprinkle with remaining 1/4 cup basil.