Nectarine Buttermilk Upside-Down Cake

Preparation

1. Step 1

   Position a rack in the center of the oven and heat to 350°F.

   Step 2

   In a small saucepan, melt 6 tablespoons of the butter over medium-low heat. Stir in the brown sugar and cook, stirring, until the sugar has melted and the mixture is smooth, about 4 minutes. Transfer to a round 9-inch-wide by 3-inch-tall cake pan, spreading the mixture evenly across the bottom. Arrange the nectarine slices on top of the butter mixture in an overlapping spiral pattern. When you’ve covered the bottom, build another layer of fruit on top, filling in any blank spaces left by the first layer. Set aside.

   Step 3

   In a medium bowl, whisk together the flour, baking powder, and salt and set aside.

   Step 4

   In a stand mixer fitted with the paddle attachment, combine the remaining 6 tablespoons butter with the granulated sugar. Beat on medium-high speed until light and fluffy, about 2 minutes. With the motor running, add the eggs, one at a time, beating well after each addition and scraping the bowl as needed.

   Step 5

   Add the flour mixture and mix on low speed just until the batter comes together, about 15 seconds. Add the buttermilk and vanilla and mix again just until blended, about 10 seconds longer.

   Step 6

   Spoon the batter over the fruit and gently smooth the top, being careful not to dislodge the fruit.

   Step 7

   Bake until a wooden skewer inserted into the cake comes out clean, about 1 hour.

   Step 8

   Let cool on a rack for 30 minutes. Then run a small knife around the edge of the pan and turn out onto a large plate or cake stand. The cake may resist releasing from the pan—if so, give the inverted pan a gentle up-and-down shake to help the cake slide out.

   Step 9

   Let cool completely before serving.