Apple Upside Down Cake

Found on kitchenmusings.com - Adapted from Rose Levy Berenbaum's recipe in Rose's Heavenly Cakes
http://kitchenmusings.com/2009/10/bring-on-the-apples.html

Apple and Walnut Filling
3 1/4 c sliced apples (about 2 large)
1 t lemon juice, freshly squeezed
1/3 c light brown sugar, firmly packed, divided
4 T unsalted butter, divided
2/3 c pecan halves

One 9×2-inch round cake pan bottom coated with shortening, topped with a parchment round
baking stone optional

Preheat the oven, twenty minutes or more before baking, set an oven rack in the lower third of the oven, set a baking stone, if using, on the rack and preheat the oven to 350F.

Make the apple topping:
In a medium bowl, toss together the apples, lemon juice, and 2 tablespoons of the brown sugar. Allow the mixture to sit for at least 30 minutes or up to 1 1/2 hours. Drain the apples, reserving their liquid.

In a small heavy saucepan, preferably nonstick, melt the butter. Use about 1 tablespoon to coat the parchment-lined bottom and the sides of the cake pan.

Add the remaining brown sugar and the reserved liquid that has drained from the apples to the butter remaining in the saucepan. Bring to a boil, stirring constantly with a light-colored silicone spatula, then stop stirring, but leave the spatula in place to judge the color, and simmer for about 3 minutes, until bubbling thickly and deep amber in color.

Pour this mixture (do not scrape) into the prepared cake pan, tilting to coat the entire bottom. Don’t worry if the mixture hardens; it will melt during baking. Place the apple slices, overlapping slightly, on the bottom and around the sides of the pan. Set aside.

Toast the pecans:
Spread the pecans evenly on a baking sheet and bake for about 7 minutes to enhance their flavor. Stir once or twice to ensure even toasting and avoid over-browning. Cool completely. Chop coarsely and set aside.

Batter
3 large egg yolks, at room temperature
1/2 c Greek yogurt, divided
1 1/4 t pure vanilla extract
1 1/3 c all purpose flour, sifted into the cup and leveled off
3/4 c superfine sugar
3/4 t baking powder
1/4 t baking soda
1/4 t salt
9 T unsalted butter

Mix the liquid ingredients. In a medium bowl, whisk the yolks, 2 tbs. of the yogurt, and the vanilla just until combined.

Make the batter:
In a bowl of a stand mixer fitted with the flat beater, mix the flour, sugar, baking powder, baking soda, and salt on low speed for 30 seconds. Add the butter and the remaining yogurt. Mix on low speed until the dry ingredients are moistened. Raise the speed to medium and beat for 1 1/2 minutes. Scrape down the sides of the bowl.

Starting on medium-low speed, gradually add the egg mixture to the batter in two parts, beating on medium speed for 30 seconds after each addition to incorporate the ingredients and strengthen the structure. Scrape down the sides of the bowl. Using a silicone spatula, drop the batter in big blobs on top of the apples. then smooth the surface evenly with a small offset spatula while keeping the apples in an attractive pattern.

Bake the cake:
Place the pan in the oven on the stone, if using it. Bake for 35 to 45 minutes, or until golden brown, a wire cake tester inserted in the center comes out clean, and the cake springs back when pressed lightly in the center.

Unmold and cool the cake:
Run a small metal spatula between the sides of the pan and the cake, pressing firmly against the pan, and invert the cake at once onto a serving plate. Leave the pan in place for 1 to 2 minutes before lifting it off. If any apple slices have stuck to the pan, use a small metal spatula to place them back on the cake. Scatter the toasted pecans on top. Serve warm or room temperature.