Apple Betty Squares

3 slices firm white sandwich bread, torn into quarters

For shortbread base:
1 1/2 sticks cold unsalted butter
2 cups all purpose flour
1/2 cup packed light brown sugar
1/2 teaspoon salt

For apple filling:
11/4 sticks unsalted butter
2 lb tart apples
2/3 cup granulated sugar
2 tablespoons all purpose flour

Preheat oven to 350F. Prepare bread crumbs: Grind bread to fine crumbs in a food processor. Spread in a shallow baking pan and toast in middle of oven, stirring once, until golden, about 5 minutes. Leave oven on.

Make shortbread base: Cut butter into 1/2 inch pieces, then pulse in a food processor with flour, brown sugar, and salt until it begins to form small lumps. Sprinkle base into a 13 by 9 inch baking pan and press evenly onto bottom.

Bake in middle of oven until golden, about 20 minutes. Prepare filling while shortbread is baking: Melt butter and keep warm.

Peel, quarter, and core apples and thinly slice quarters crosswise. Stir together sugar and flour in a small bowl.

Assemble and bake squares: Sprinkle half of sugar mixture over hot shortbread, then top with apples and sprinkle with remaining sugar mixture. Top with bread crumbs and drizzle all of butter over them.

Bake in upper third of oven, pressing down on filling with a metal spatula halfway through baking, until apples are very tender and bread crumbs are golden, 50 minutes to 1 hour total. Cool 20 minutes in pan on a rack.

Cooks’ note: Squares keep, covered and chilled, 3 days. Bring to room temperature before serving.

Makes 12 squares.