Starbucks-Style Gluten Free Apple Pound Cakes
16 tablespoons (224 g) unsalted butter, at room temperature
1 cup (200 g) sugar
9 ounces (about 4) eggs at room temperature, beaten
1 teaspoon pure vanilla extract (or 1/2 teaspoon vanilla extract + 1/2 teaspoon almond extract)
1 cup 9 tablespoons (220 g) all-purpose gluten free flour (I used Better Batter)
1/2 teaspoon xanthan gum (omit if your blend already contains it)
1 1/2 teaspoons kosher salt
1 teaspoon ground cinnamon
2 tablespoons (28 g) packed light brown sugar
1 teaspoon ground cinnamon
1/4 teaspoon freshly ground nutmeg
1/8 teaspoon kosher salt
2 cups diced, peeled firm apples (from about 2 medium-size apples—Granny Smith works great, so do Empire)
Preheat your oven to 325°F. Grease well a 6-well round cake panel pan, or a standard 12-cup muffin tin, and set it aside.
First, make the cake batter. In the bowl of a stand mixer fitted with the paddle attachment or a large bowl with a handheld mixer, cream the butter on medium-high speed until it is light and fluffy. Add the sugar, and then the eggs (slowly, while the mixer is on low speed) and vanilla, beating after each addition until well-combined. Turn the mixer speed up to medium-high, and beat until smooth.
In a small bowl, place the flour blend, xanthan gum, salt, and cinnamon, and whisk to combine well. Add the flour mixture, about ¼ cup at a time, to the mixer bowl with the wet ingredients, and mix until just combined. The batter will be thick but soft and smooth. Divide the mixture evenly among the wells of the cake panel pan or muffin tin, and shake the pan back and forth to distribute the batter evenly in each well. Carefully bang the bottom of the pan a few times on the counter to release any air bubbles.
Make the topping. In a small bowl, combine the sugar, cinnamon, nutmeg and salt and whisk to combine, working out any lumps in the brown sugar. Add the diced apple, and mix to combine well. Divide the apple topping evenly among the tops of the batter in the wells of the muffin tin or cake panel pan, pressing the apple pieces down gently but firmly to help the apples adhere. The apple pieces should be in an even layer on top of the batter.
Bake the cakes. Place in the center of the preheated oven and bake until a toothpick inserted in the center of each cake comes out clean, or with a few moist crumbs attached (about 30 minutes for the cake panel pan, or 22 minutes for the muffin tin). The very top of each cake around the apple pieces may seem slightly wet, but the cakes are done as long as the cakes feel firm to the touch. Allow to cool for at least 10 minutes in the pan before transferring to a wire rack to cool completely.