Step 1

Preheat the oven to 350ºF. In a small bowl, whisk together the flour, baking powder, ½ teaspoon salt, and cinnamon. In another small bowl, whisk together the sour cream, oil, and vanilla. Set both aside. In a medium bowl, whisk together the sugar and eggs until foamy, about 2 minutes.

Step 2

Gently stir in half the flour mixture, then stir in half the sour cream mixture. Stir in the remaining flour mixture and then the remaining sour cream mixture until just combined. Set aside.

Step 3

Butter the bottom and sides of an 8-inch cast iron skillet or springform pan and add honey, swirling the pan around to ensure it covers as much of the pan as possible. Sprinkle with ¼ teaspoon salt.

Step 4

Arrange the sliced apples over the honey, overlapping them to fit in the pan. Pour the cake batter over the apples and tap the pan a few times to get rid of any large bubbles. Bake until the cake is golden brown and springs back when lightly touched with your finger, about 30 minutes.

Step 5

Let the cake cool in the pan for 10 minutes, then run an offset spatula or knife around the pan and invert cake onto a cooling rack (or unmold then invert, if using a springform). Let cool for at least an additional 20 minutes before transferring to a platter and sprinkling with flaky salt.

Step 6

If you’d like, whisk extra sour cream with honey to taste, and dollop on the cake slices before serving.