First peel and slice the tomatoes and lay down on a few sheets of paper towels and let sit for at least ten minutes.
While drying, make the pie crust. Using a pastry blender or fork, cut the shortening into the flour until the clumps are pea sized. Then one tablespoon at a time, add cold water to the mixture and lightly mix with a fork. Keep adding water until the dough starts to pull together and is moistened throughout. Roll the dough out on a lightly floured surface and roll into a 9 inch deep dish pie crust. Crimp the sides up and back for 15 minutes in a 450 °F (220 °C) oven.
Once the pie is baked, turn the oven down to 350 °F (175 °C). Then, take the tomato slices and layer tomatoes and a teaspoon of basil. Keep layering until all the tomatoes are in.
Combine cheeses and mayonnaise. Spoon over tomatoes and spread out evenly.
Bake for 20-25 minutes or until the top is lightly browned. Can be served hot or room temperature.
There are 301 calories in 1 serving of Cheesy Tomato Pie.