A Sweet and Savory Upside Down Cake
Onions in a cake? YES! We had testers who couldn’t tell the Vidalia onions were there – they sort of melt into to the cake – but everyone loved the sweet and savory aspects to this take on the classic upside down cake. Try this for brunch with a slice of Brie melted on top. Oh yeah. Or a slice of sharp Manchego. We used a Lodge cast-iron skillet to make this cake but any heavy, ovenproof skillet will work. (Make sure your handle is ovenproof!) If you love Vidalia onions make sure to check out our Caramelized Vidalia Onion Bacon Cornbread, too.
- 2 Vidalia onions, sliced thinly
- 2 tablespoons unsalted butter
- 5 tablespoons unsalted butter
- ¾ cup firmly packed light brown sugar
- ⅛ teaspoon cinnamon
- 2 sweet, firm apples, such as Braeburn, peeled and sliced into ¼-inch slices
- ¾ cup sugar
- 2 large eggs
- ¾ cup all-purpose flour
- ½ teaspoon baking powder
- ⅛ teaspoon salt
- ¼ cup buttermilk
- For the Caramelized Onions: Position rack in center of oven. Preheat oven to 325°F.
- Using a 9 to 10-inch cast-iron pan, melt the 2 tablespoons butter then add the onions and cook on medium heat until golden and caramelized, stirring often. This might take up to 15 minutes; don’t rush this step and keep heat low/medium so as not to burn the onions. They should be a rich golden mahogany color when done. Go by look, not time. Scrape onions out onto a plate and wipe out pan with a paper towel before proceeding.
- For the cake: Melt the 5 tablespoons butter then add the brown sugar, stirring to combine. Remove from heat and stir in the cinnamon. Arrange apple slices in a radiating spoke pattern (see image) and fill in the center as well. Spread caramelized onions evenly over apples; set aside.
- Beat sugar and eggs until creamy. Stir in the flour, baking powder and salt just until beginning to combine, then add buttermilk and continue stirring gently until combined.
- Pour batter over onions and spread evenly with a small offset spatula.
- Bake for 35 to 40 minutes or just until a toothpick tests clean. Loosen the edges of the cake from the pan and invert onto a large, flat serving plate. If any apple or onion pieces stick to the pan, simply pry them loose and put into place. Serve as soon as possible. Cake is best served the same day and may be served warm or at room temperature.