Apple Tart with Whole Wheat Crust

1. Prepare the Crust

In a large bowl, whisk together the all-purpose flour, whole wheat flour, sugar, and a pinch of kosher salt. Grate the frozen unsalted butter and add it to the flour mixture, then gradually add the very cold water, kneading gently until the dough is just smooth and cohesive. Form the dough into a disk, wrap it in plastic wrap, and refrigerate for 45 minutes.

2. Preheat Oven and Prepare Applesauce Mixture

Preheat the oven to 400°F and line a large rimmed baking sheet with parchment paper. In a small bowl, whisk together the applesauce with the freshly grated ginger.

3. Prepare Apple Filling

Peel, core, and thinly slice the Granny Smith apples. Toss the apple slices in a large bowl with fresh lemon juice, a pinch of salt, and sugar.

4. Assemble and Bake the Tart

Roll out the chilled dough on a floured work surface and transfer it onto the prepared baking sheet. Spread the ginger applesauce mixture over the dough, leaving a border around the edges. Arrange the apple slices on top of the applesauce. Beat the egg with water and brush the mixture over the edges of the dough. Bake for about 1 hour until the crust is browned and apples are tender.

5. Cool and Serve

Transfer the baked tart to a wire rack to cool completely before serving. The tart can be stored covered at room temperature for up to two days.