Gluten-Free Caramelized Apple Upside-Down Cake

recipe by: Sarah Menanix

yields: slices, 9-inch round cake

prep time: 20

cook time: 55

total time: 1 15

This gluten-free apple upside-down cake has the softest crumb with wonderful spice flavor. Cinnamon-kissed caramelized apples bake into the bottom of the cake, which is then flipped over while warm to reveal the stunning top.

5 from 3 reviews

Ingredients

Caramelized Apple Topping

½ cup light brown sugar
¼ cup unsalted butter
½ teaspoon vanilla bean paste, or vanilla extract
¼ teaspoon ground cinnamon
Pinch kosher salt
2 medium Granny Smith apples, peeled, cut off the core, and cut into ⅛ to ¼-inch thick slices

Gluten-Free Spiced Cake

67 g (½ cup + 2 tablespoons) Bob’s Red Mill gluten-free oat flour, or sub with 72g sorghum flour
70 g (¼ cup + 3 tablespoons) sweet rice flour, also called mochiko; do not substitute white or brown rice flour
56 g (½ cup) Bob’s Red Mill tapioca flour
46 g (¼ cup + 1 tablespoons) Bob’s Red Mill teff flour
¾ teaspoon xanthan gum
1¼ teaspoon ground cinnamon
¼ teaspoon ground nutmeg
1 teaspoon baking powder
½ teaspoon baking soda
½ teaspoon kosher salt
¼ cup + 2 tablespoons (85 g) unsalted butter, room temperature
220 g (1 cup + 2 tablespoons) granulated sugar
2 large eggs, room temperature
2 teaspoons pure vanilla extract
⅔ cup (160 g) whole milk, room temperature
⅓ cup (80 g) sour cream, room temperature

INSTRUCTIONS

Preheat oven to 350°F. Lightly grease a 9-inch round aluminum cake pan with 2-inch sides with vegetable oil and line it with a round of parchment paper. Set aside. See note for other sizes of pans.
Combine the brown sugar and butter in a small saucepan over medium heat. Cook, stirring until the butter and sugar are just melted, about 1-2 minutes. Mix in the vanilla bean paste and salt. Pour the caramel into the prepared cake pan and spread it into an even layer.
Arrange the apple slices in concentric overlapping circles on top of the caramel, squeezing in as many as will fit (see picture above).
Sift together the oat flour, sweet rice flour, tapioca flour, teff flour, xanthan gum, cinnamon, baking powder, baking soda, and salt.
In the bowl of a stand mixer fitted with the paddle attachment or a large mixing bowl with a hand mixer, cream together the butter and sugar over medium-high speed until light and fluffy, 3-5 minutes.
Add the eggs, one at a time, mixing after each addition and scraping down the sides as needed. Add the vanilla extract.
With the mixer on low, add the dry ingredients in three additions, alternating with the milk and sour cream, scraping down the sides as needed. Mix until just combined.
Pour the cake batter over the apples, smoothing out the top.
Bake for 52-57 minutes, until the center springs back when gently touched and a toothpick comes out clean or with just a few crumbs.
Let cool In the pan for 5-10 minutes (but no longer or the caramel will firm up and stick to the pan!). Set a plate or baking sheet nearby for catching drips. Run a knife around the outside edge, place a wire rack over the top and, holding the wire rack and cake pan together with oven mitts, carefully flip the cake right-side up, setting it over a plate or baking sheet to catch any caramel spills. Remove the parchment paper. Spoon any caramel left in the pan over the top, and if any apple pieces remain stuck to the top, carefully put them back on the cake. Let cool for at least 30 minutes before slicing and serving.

Notes

Alternative Pan Sizes: A 8x8 square cake pan or 10-inch round cake pan will work too, as will a 9-inch cast iron skillet or springform pan. If using a springform pan, place a baking sheet underneath to catch any leaks. If using a 10-inch round baking pan or a cast-iron skillet, your bake time will be less. For a 10-inch round, start checking for doneness at 40 minutes. For a cast iron skillet, check for doneness at 45 minutes. I do not recommend using a glass cake pan as it heats up faster and is more likely to overcook the outside of the cake before the center is fully baked.

Substitution for oat flour: Sub in by weight with gluten-free sorghum flour or Bob's Red Mill 1-to-1 all-purpose gluten-free flour blend. I've made the cake with sorghum flour rather than oat flour and it's equally as delicious!

Substitution for teff flour, sub in by weight: You can sub in 15g more each of sorghum flour, sweet rice flour, and tapioca flour, but your cake will turn out lighter in color and less flavorful. You could also sub in chestnut flour, millet flour, or Bob's Red Mill all-purpose gluten-free flour.