Step 1: Preheat the Oven and Prepare Pans

Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans or line them with parchment paper for easy removal.

Step 2: Mix the Dry Ingredients

In a medium bowl, whisk together the flour, baking soda, baking powder, and salt. Set aside.

Step 3: Cream the Butter and Sugar

In a large mixing bowl, using an electric mixer, cream the softened butter and granulated sugar on medium speed until light and fluffy—about 3-4 minutes. This step is key for creating a soft, tender cake.

Step 4: Add the Eggs and Vanilla

Add the eggs, one at a time, beating well after each addition. Scrape down the sides of the bowl as needed. Add the vanilla extract and mix until incorporated.

Step 5: Alternate Adding the Dry Ingredients and Buttermilk

With the mixer on low, add one-third of the dry ingredients to the butter mixture, followed by half of the buttermilk. Mix until just combined. Repeat this process, alternating between the flour mixture and buttermilk, ending with the final third of the dry ingredients. Be careful not to overmix—just mix until everything is incorporated.

Step 6: Bake the Cake Layers

Divide the batter evenly between the prepared cake pans and smooth the tops with a spatula. Bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean. Once baked, let the cakes cool in the pans for 10 minutes before transferring them to a wire rack to cool completely.

Step 7: Prepare the Caramel Frosting

While the cakes cool, make the caramel frosting. In a medium saucepan, melt the butter over medium heat. Add the brown sugar and heavy cream, stirring constantly until the mixture comes to a boil. Allow it to boil for about 2 minutes while stirring, then remove from heat.

Step 8: Cool and Beat the Frosting

Stir in the vanilla extract and let the caramel mixture cool for about 10 minutes. After it has cooled slightly, transfer the mixture to a large bowl. Gradually add the sifted powdered sugar, beating on medium speed until the frosting becomes smooth and spreadable. If the frosting is too thick, you can add a tablespoon of heavy cream to reach your desired consistency.

Step 9: Frost the Cake

Once the cake layers are completely cooled, place one layer on a serving platter and spread a generous amount of caramel frosting on top. Place the second cake layer on top and frost the entire cake, covering both the top and sides with a thick layer of caramel frosting.