Preheat your oven to 375°F (190°C). Fit the refrigerated pie crust into a 9-inch pie pan and blind-bake for 8-10 minutes until lightly golden. Set aside to cool.

Cook thick-cut bacon in a large skillet over medium heat until crispy, about 6-8 minutes. Remove with a slotted spoon, crumble, and reserve 1 tablespoon of drippings.

Add sliced sweet onions to the skillet with reserved drippings. Sauté over medium-low heat for 10-15 minutes until soft and golden brown.

Slice ripe tomatoes and sprinkle with salt. Let sit for about 10 minutes, then pat dry with paper towels.

In the pre-baked pie crust, layer half of the crumbled bacon, caramelized onions, and salted tomatoes. Repeat the layering process with the remaining bacon, onions, and tomatoes.

In a bowl, combine mayonnaise, shredded cheddar, shredded mozzarella, fresh basil, and salt & pepper. Mix until smooth and creamy; spread over the pie filling.

Bake in the preheated oven for 30-35 minutes until the topping is bubbly and golden brown.

Allow the pie to rest for about 10 minutes before slicing. Garnish with fresh herbs and serve warm or at room temperature.