Preheat your oven to 350°F (175°C).
Place the sliced tomatoes in a single layer on paper towels. Sprinkle with salt and let them sit for about 10 minutes to draw out excess moisture. Pat the tomatoes dry with additional paper towels.
In the pre-baked pie crust, layer half of the tomato slices, followed by half of the chopped basil and green onions.
Mix together the mozzarella and cheddar cheeses, then sprinkle half of this mixture over the tomato layer in the pie crust.
Repeat the layers with the remaining tomato slices, basil, green onions, and cheese mixture.
In a small bowl, mix together the mayonnaise, grated Parmesan cheese, and black pepper. Spread this mixture evenly over the top of the pie, covering the cheese and tomatoes.
Bake the pie in the preheated oven for 30-35 minutes, or until the top is golden and bubbly.
Allow the pie to cool for about 10 minutes before slicing and serving.
Variations & Tips
For a healthier twist, you can use a whole wheat pie crust and reduce the amount of mayonnaise by substituting half of it with Greek yogurt. If you enjoy a more robust flavor, try adding a few cloves of minced garlic to the tomato layers or a handful of caramelized onions. For added protein, consider incorporating a layer of cooked and crumbled bacon or sausage before adding the tomatoes. If fresh basil is not available, a combination of dried Italian herbs can be used as a substitute.