Recipe Instructions:
Unsalted butter, at room temperature, or oil for greasing the pan
3 large eggs, at room temperature
1 cup (213 grams) light brown sugar
1/4 teaspoon kosher salt
3 Granny Smith apples (about 198 grams or 7 ounces each)
1 cup plus 2 tablespoons (134 grams) white whole-wheat flour
Heat the oven to 350°F. Butter the bottom (but not the sides) of an 8-inch springform pan.
Combine the eggs, light brown sugar, and salt in the bowl of a stand mixer fitted with the whisk attachment. Start on low, then raise the speed to medium-high, and beat for about 8 minutes, until the mixture is a pale tan in color and super fluffy.
While that’s going, peel the apples, then cut them into ½-inch pieces (they don’t have to be perfect cubes but they should all be a similar size). This should yield about 4 cups of apple pieces.
When the egg-sugar mixture is done mixing, remove the bowl from the stand mixture and add the flour. Use a flexible spatula to gently fold in the flour until it’s almost incorporated. Add the apples and fold those in, too. Scrape the batter into the prepared pan.
Bake for about 1 hour and 15 minutes, or until the top is browned and a cake tester comes out completely clean. Cool in the pan for about 30 minutes, then run a knife around the edge to loosen the cake, and unhinge the outside.
Serve the cake in big wedges, warm or at room temperature, with confectioners’ sugar dusted on top, and crème fraîche (or whipped cream or Greek yogurt) plopped alongside. This is best the day it’s made.