Preheat oven to 350 degrees Fahrenheit. Grease and line with parchment paper 3 8-inch round cake pans.
Sift flour, baking powder, and salt. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment, or in a large mixing bowl using a hand mixer, beat together the butter, oil, and Domino® Golden Sugar until light and fluffy.
Add the eggs one at a time, mixing well after each addition. Mix in the vanilla extract and half of the buttermilk.
Add half of the dry ingredients and mix on low speed until just combined. Mix in the remaining buttermilk. Finally, add the remaining dry ingredients and mix until there are no more dry spots and the batter is smooth.
Divide the batter evenly into the prepared cake pans and bake for 35-40 minutes, or until a wooden skewer inserted into the center comes out clean.
While the cake layers are cooling, prepare the salted caramel and buttercream.
To make the salted caramel, heat the Domino® Golden Sugar in a large heavy bottom saucepan over medium heat. Once the sugar begins to melt, whisk the sugar to get rid of any clumps. After about 10 minutes, the sugar should be completely melted and an amber color. Remove the saucepan from heat and immediately whisk in the butter and cream. Stir in the salt. Pour the mixture through a sieve into a heatproof bowl to remove any lumps of sugar. Set aside to cool.
For the buttercream, use a stand mixer or a hand mixer to beat the butter for 3-4 minutes, until pale and creamy. Add the Domino® Powdered Sugar and continue to beat for another 2-3 minutes until smooth. Beat in 2/3 cup of cooled salted caramel sauce until the buttercream is fluffy.
Place your first layer onto a cake board or cake stand. Spread a generous amount of buttercream over the cake and then drizzle 2 tablespoons salted caramel sauce on top. Place the second layer and repeat process. Top with the final cake layer. Cover the cake with a thin layer of buttercream and chill for 30 minutes. Add a final layer of buttercream to cover the cake. Use a large angled spatula to cream a smooth and even finish. Chill for another 10 minutes. Pour the remaining caramel over the top of the cake to create a dripping effect and sprinkle with more sea salt.
Use a squeeze bottle to create a “clean” drizzle look over the cake.