Step 1

In a heavy bottomed sauce pan, heat the sugar on medium low heat until its completely melted, swirling the pan gently every 20 seconds or so. The sugar will start to form clumps before melting slowly. Be patient and keep an eye on it to make sure it does not burn.

Step 2

Once melted, remove from heat immediately and stir in the butter. The mixture will violently bubble. You’re doing it right.

Step 3

Next, pour in the heavy cream and sea salt. Stir until everything is combined.

Step 4

Pour into a container and allow to cool completely before using. We recommend doing this step a day in advance so that the caramel is completely cool and easy to work with when you make your caramel cake.

Step 5

Preheat the oven to 325°F and grease and flour  3 6 inch pans Set aside.

Step 6

In a large mixing bowl fitted with a whisk attachment, beat the softened butter and oil together until they become homogenous, about 3 minutes. This will not work if your butter is not completely room temperature.

Step 7

Slowly add the granulated sugar to the oil and butter, beating on high until the mixture is light and fluffy and turns a very pale yellow, about 3 minutes.

Step 8

Add the eggs in one at time, scraping down the bowl in between each addition. Add the vanilla extract. Beat the mixture on high for 3 minutes more to incorporate as much air as possible.

Step 9

In separate bowl sift together the cake flour, salt, and baking powder. Alternate mixing in the dry ingredients and the buttermilk in 4 batches, starting with the buttermilk and ending with the dry ingredients. It’s okay if the batter still has a few lumps in it–you don’t want to over mix it.

Step 10

Split the batter evenly into the prepared pans and back for 30 minutes or until the cake is a lightly golden brown and springs back when pressed. This will depend on your oven. Take out of the oven and transfer to a cooling rack. Let the cakes cool completely before using.

Step 11

While the cakes cool, make the buttercream.

Step 12

Place the softened butter and powdered sugar in a stand mixer fitted with a whisk attachment. Beat the butter and sugar together until combined. The mixture will be thick.

Step 13

Add the milk, salt, and vanilla extract and turn the mixer on high. Beat for 3 minutes. Scrape down the sides of the bowl using a rubber spatula. Beat for 2 more minutes until frosting is thick and fluffy.

Step 14

Transfer the buttercream to a large piping bag and set aside.

Step 15

Bring the caramel to room temperature and set aside a half cup of caramel to use on the outside of the cake. Reserve the rest for the filling.

Step 16

Place the first cake round on a cake stand, then pipe a border around the the top of the cake to create a barrier to hold in the caramel. Pour half of the caramel for the filling on top of the cake, using an offset spatula to spread the filling to the buttercream border. Place the second cake on top and repeat. Place the third layer on top and use the frosting to frost the tops and edges of the cake. Take the reserved 1/2 cup of caramel and use an offset spatula to swirl the caramel into the buttercream or dab it along the sides of the cake, kind of link a paint palette. drizzle the cake with any additional caramel. Refrigerate the cake until ready to serve!