This is a Plum Cake you’ll want to make time and time again. I have… and do. Beginning in September and for as long as the fresh plums show up in my market.
Preheat the oven to 350°F and grease a 9-inch cake pan. A springform pan works great with this cake!
In a large bowl, whisk together the flour, baking powder, cinnamon, salt, and cardamom.
With an electric or stand mixer, cream together the butter and 1 cup sugar, beating until it is light and fluffy, about 3 minutes. Add the egg, vanilla and sour cream to the bowl, mix on low speed until just combined. Gradually add the flour mixture to the butter mixture and mix until smooth.
Transfer cake batter to prepared pan. Top with sliced plums and sprinkle 2 tablespoons sugar over the cake top. Bake for 35-40 minutes, or until a tester inserted in the middle comes out clean.
Remove the cake from the oven, run a sharp knife around the edges of the cake while it’s still hot to loosen it from the pan. Let the cake cool completely on a rack. Dust with confectioners’ sugar, slice and serve with ice cream or whipped cream if desired.