Heat oven to 375°. Place sliced
tomatoes in a single layer on paper towels. Sprinkle one side of tomatoes with 1/4 tsp of the salt; let stand for 10 minutes. Gently pat salted side of tomatoes with paper towels to absorb some of the moisture. Flip tomatoes and sprinkle with
remaining 1/4 tsp of the salt.
Meanwhile, fit piecrust into a 9-inch pie plate. Sprinkle bread
crumbs evenly on the bottom. Place half the mozzarella over the bread crumbs, along with a third of the tomatoes and a third of the basil. Sprinkle with 2 tbsp of the Parmesan. Layer with a third of the tomatoes, a third of the basil and remaining mozzarella. Layer with remaining tomatoes, basil and
Parmesan. Season with pepper and, if desired, brush edges of crust with beaten egg.
Bake at 375° for 40 to 45 minutes, until crust is browned. Cool 10 to 15 minutes before slicing.
Pie will have moisture. For a less wet pie, seed the tomatoes.