Nutrition per serving may change if servings are adjusted.
⅓ cup packed dark brown sugar
4 tablespoons unsalted butter, at room temperature, divided
6 Pixie tangerines or clementines, unpeeled
1½ cups white whole-wheat flour
1½ teaspoons baking powder
½ teaspoon baking soda
½ teaspoon salt
2 tablespoons canola oil
⅔ cup granulated sugar
2 large eggs
2 teaspoons vanilla extract
¾ cup buttermilk
Preheat oven to 350°F. Coat an 8- to 9-inch round cake pan with cooking spray; line the bottom with parchment paper and spray the paper.
Heat brown sugar and 2 tablespoons butter in a small pan over medium heat until the butter melts. Spread in the prepared pan, leaving a ¼-inch border around the edge. Grate ½ teaspoon zest from 1 tangerine (or clementine); set aside. Cut a thin slice off the stem end of each fruit, then slice into ¼-inch rounds. Place a slice in the center of the pan; arrange the remaining slices in slightly overlapping circles out to the edge.
Whisk flour, baking powder, baking soda and salt in a medium bowl.
Beat the remaining 2 tablespoons butter, oil and granulated sugar in a large bowl with an electric mixer until light and fluffy, about 2 minutes. Beat in eggs, one at a time. Mix in vanilla and the zest. With the mixer on low, blend in the flour mixture alternately with buttermilk, making 3 additions of the flour mixture and 2 of the buttermilk and mixing until just combined. Pour the batter into the pan, smoothing the top.
Bake until a toothpick inserted in the center comes out clean, 40 to 50 minutes. Cool for 10 minutes on a wire rack. Run a knife around the edge of the pan and invert the cake onto a cake plate.
Make Ahead Tip: Loosely wrap and store at room temperature for up to 1 day.
251 calories;9 g fat(4 g sat); 3 g fiber; 40 g carbohydrates; 5 g protein; 17 mcg folate; 50 mg cholesterol; 26 g sugars; 21 g added sugars; 205 IU vitamin A; 22 mg vitamin C; 89 mg calcium; 3 mg iron; 305 mg sodium; 157 mg potassium
Vitamin C (37% daily value)
Carbohydrate Servings: 2½
Exchanges: 1 starch, ½ fruit, 1½ other carbohydrate, 1½ fat