2½ pounds fresh heirloom tomatoes, cut into ¼-inch-thick slices
1½ teaspoons kosher salt, divided
1 (14.1-ounce) package refrigerated piecrusts
2 teaspoons water
1 cup shredded Gruyère cheese
1½ cups shredded sharp Cheddar cheese, divided
¾ cup mayonnaise
1 tablespoon fresh thyme
½ teaspoon ground black pepper
1 large egg
4 teaspoons fine Italian-seasoned bread crumbs, divided
Garnish: fresh thyme, ground black pepper
Instructions
In a 10-inch skillet, cook bacon over medium heat until crisp. Remove from skillet, and let drain on paper towels. Reserve 1 tablespoon drippings in skillet and heat over medium-high heat. Add onion; cook until lightly browned around the edges, about 6 minutes. Spoon onion into a small bowl; let cool completely.
Line 2 baking sheets with paper towels. Arrange tomato slices in a single layer on prepared pans; sprinkle with 1 teaspoon salt. Let stand for 30 minutes. Pat tomatoes dry with additional paper towels.
Preheat oven to 425°.
On a lightly floured surface, unroll 1 piecrust. Lightly brush with 2 teaspoons water. Top with remaining piecrust. Roll piecrust into a 14-inch circle. Transfer dough to a 10-inch deep-dish pie dish, pressing into bottom and up sides. Trim excess dough to ½-inch from edge of dish. Fold edges under and crimp as desired.
Into bowl with onion, stir in Gruyère, 1 cup Cheddar, mayonnaise, thyme, pepper, egg, and remaining ½ teaspoon salt. Spread half of mayonnaise mixture in bottom of prepared crust. Sprinkle with 2 teaspoons bread crumbs. Arrange half of tomatoes, overlapping slightly, on top. Repeat layers once. Top with remaining ½ cup Cheddar.
Bake for 15 minutes. Reduce oven temperature to 375°. Loosely cover with foil, and bake until golden brown, about 30 minutes more. Let cool for at least 2 hours on a wire rack. Sprinkle with bacon. Garnish with thyme and pepper, if desired.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/ultimate-tomato-pie/