This bourbon caramel cake has fluffy bourbon brown sugar layers and an old fashioned Southern caramel frosting!
For the cake:
½ cup unsalted butter, at room temperature
¼ cup canola oil
½ cup sugar
¼ cup brown sugar, packed
1 large egg, at room temperature
1 large egg yolk, at room temperature
1–3/4 cups cake flour
½ teaspoon baking powder
½ teaspoon baking soda
½ teaspoon salt
½ cup milk, at room temperature
2 tablespoons bourbon
1 teaspoon vanilla extract
For the frosting:
¾ cup unsalted butter, divided
2 cups light brown sugar, packed
½ cup heavy whipping cream, plus more to thin out icing
2–1/2 cups powdered sugar
½ teaspoon kosher salt
To prepare the cake:
Preheat the oven to 325 (if using a dark pan like me. Otherwise, you can go up to 350 but bake time will be shorter). Lightly grease a 9” square pan and cut out a sheet of parchment paper to fit into the bottom of it. Set aside.
In a large bowl or the bowl of a stand mixer, cream together the butter, canola oil, sugar, and brown sugar until smooth, about a minute and a half. Add the egg and yolk and stir until combined. Scrape the sides of the bowl and stir in any unincorporated bits. Add half of the cake flour, the baking powder, baking soda, and salt and stir on low to combine. Add ¼ cup of the milk as well as the bourbon and vanilla. Stir on low. Add the remaining cake flour and milk and stir on low just until combined. Fold in any unincorporated bits. Spread the batter into the prepared pan and bake in the middle of the oven for about 35-37 minutes or until the cake has puffed, turned golden, and a toothpick inserted just barely comes out clean. Don’t overbake! Set aside to cool completely.
When ready to frost the cake (see notes), remove the cake from the pan, use a serrated knife to trim off any dome, and cut in half lengthwise to create two 4.5”x9” cakes. Prepare your frosting as follows.
In a medium saucepan, combine ½ cup butter and the brown sugar over low heat and stir the mixture until the butter and sugar are combined and smooth but the mixture hasn’t begun to boil. Turn the heat up to medium and stop stirring. Cook until bubbles appear on the sides and middle of the pot. Remove from heat and carefully stir in ½ cup cream. Whisk the cream in to incorporate, but be careful, as the mixture may splatter. Place back on heat and bring to a bubble again then remove from heat. Pour the mixture into the bowl of your stand mixer and add the powdered sugar. Beat on medium speed with the paddle attachment until the mixture has cooled to a warm temperature. Add the remaining butter and beat ad additional minute. At this point, assess the texture. The frosting should be slightly warm and very loose. The frosting will set up as it cools, so you’ll need to add a bit of additional cream or milk to thin it out. I usually find 2 tablespoons is the perfect amount, but you can decide. Dollop a little bit of frosting on your serving platter or plate and place the first “layer” of cake down. Spread additional frosting on top to adhere the second layer and observe how it sets up as it cools. At this time, if the frosting sets up too firm and you want to add a little more milk, you can gently reheat it for a few seconds in the microwave and then add additional milk. Frost the cake and allow to cool before enjoying! Please note this frosting is way different to work with from traditional buttercreams, but you can briefly reheat the frosting to get it smooth enough to frost again. Just don’t overheat!
I like to work with chilled cakes. You can pop these layers in the freezer to achieve, if desired.