In alternating layers, fill pastry shell with tomatoes, basil, scallions, bacon, garlic powder, oregano, and red pepper. In a small bowl, mix cheese with mayonnaise. Spread mixture over top of pie. Cover loosely with aluminum foil.
Bake in preheated oven for 30 minutes. Remove foil from top of pie and bake an additional 30 minutes. Serve warm or cold.