Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.

In a mixing bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy.

Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.

In another bowl, whisk together the flour, baking soda, and salt. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.

Fold in the chocolate chips.

Divide the batter evenly between the prepared pans and smooth the tops.

Bake for 25-30 minutes or until a toothpick inserted into the center comes out clean.

Allow the cakes to cool in the pans for 10 minutes, then transfer to a wire rack to cool completely.

In a mixing bowl, beat the softened butter until creamy.

Gradually add the powdered sugar, mixing on low speed until combined.

Add the heavy cream and vanilla extract, then beat on high speed until the frosting is light and fluffy.

Once the cakes are completely cool, place one layer on a serving plate.

Spread a layer of buttercream frosting on top of the first cake layer.

Place the second cake layer on top and frost the top and sides of the cake with the remaining buttercream.

Decorate with additional chocolate chips if desired.