Instructions

1. Preheat oven to 325 degrees F.
2. In a medium bowl, whisk together flour, baking powder and salt. Set mixture aside.
3. In the bowl of a stand-up mixer fitted with the paddle attachment, combine 6 tablespoons of softened butter, granulated sugar, orange zest, Grand Marnier or Cointreau, cinnamon and ginger. Blend on medium speed for 4 minutes, or until the batter is smooth.
4. Add eggs and almond extract. Mix for another minute on medium speed, stopping at least once to scrape down the sides of the bowl.
5. Alternating between the two, gradually add flour mixture and sour cream to batter mixture. Mix until just combined.
6. Grease a 10-inch cast-iron skillet with the remaining 1 tablespoon butter.
7. Spread batter evenly in the greased skillet. Smooth out the top.
8. Arrange plum slices in a circular pattern on top of the cake batter.
9. Sprinkle the top evenly with brown sugar.
10. Bake for 50 to 55 minutes or until a cake tester inserted in the center of the cake comes out clean.
11. Remove cake from the oven and set aside to cool in the skillet for 15 minutes.
12. Slice and serve with a scoop of vanilla ice cream.