Rhubarb is back and we couldn’t be happier. This upside down cake has cinnamon, cardamom, and ginger tossed together with rhubarb before baking under a tasty lemon cake. Serve warm and topped with fresh whipped cream for a sweet spring dessert.
1 pound fresh rhubarb stalks, trimmed, and cut into 1-inch pieces
1 ½ cups granulated sugar, divided
2 teaspoons cornstarch
½ teaspoon ground ginger
½ teaspoon cinnamon
½ teaspoon ground cardamom
½ cup butter, plus more for the pan, divided
1 cup all-purpose flour, plus more for the pan, divided
1 cup cake flour
1 teaspoon baking powder
1 teaspoon baking soda
¼ teaspoon salt
1 cup granulated sugar
1 tablespoon lemon zest
1 cup buttermilk
1 ½ teaspoons vanilla extract
Whipped cream for serving
Line a 9-inch springform pan base with parchment. Butter and flour the pan sides and the parchment. Combine the rhubarb, ½ cup granulated sugar, ginger, cinnamon, and cornstarch in a bowl. Toss to coat; set aside.
Preheat the oven to 350˚ F.
Whisk together the flours, baking powder, baking soda, and salt in a medium mixing bowl.
In the bowl of a mixer, cream together the remaining ½ cup butter, lemon zest, and the granulated sugar until light and fluffy. Add the eggs, 1 at a time, mixing just until incorporated then add the vanilla. Add the flour mixture and buttermilk alternately in 3 batches, mixing at low speed after each addition until just combined.
Arrange coated rhubarb pieces in a single layer on the buttered parchment in pan, sprinkle over any excess sugar from bowl. Pour the batter into pan then smooth with a spatula. Gently drop the pan on the counter to remove air bubbles. Bake at 350°F until a wooden pick inserted in center comes out clean, about 1 hour. Rest for fifteen minutes then remove the ring from the springform pan. Immediately place a cooling rack on the top of the cake and flip over. Place the cooling rack over foil to collect any dripping sugar syrup. Cool completely and serve warm with whipped cream.