Ingredients:

  • 432 g (15.25 oz) yellow cake mix
  • 113 g (0.5 cup) unsalted butter, melted and cooled
  • 2 large eggs, room temperature
  • 30 g (2 tbsp) dark brown sugar, packed
  • 5 ml (1 tsp) pure vanilla extract
  • 250 g (1.5 cups) semi sweet chocolate chips
  • 1.5 g (0.25 tsp) flaky sea salt
  • 113 g (0.5 cup) unsalted butter, softened
  • 180 g (1.5 cups) powdered sugar
  • 15 ml (1 tbsp) heavy cream
  • 5 ml (1 tsp) vanilla extract

Instructions:

  1. Preheat the oven to 175°C (350°F). Grease your pan thoroughly with butter or non stick spray.
  2. Whisk the melted butter, brown sugar, and vanilla. Stir until the sugar begins to dissolve into the fat.
  3. Incorporate the room temperature eggs. Beat vigorously until the mixture looks glossy and emulsified.
  4. Fold in the yellow cake mix. Use a spatula to combine until no dry streaks of flour remain.
  5. Add the chocolate chips. Stir gently until the chips are evenly distributed through the thick dough.
  6. Press the dough into the prepared pan. Use damp fingers or the back of a spoon to level the surface.
  7. Bake for 22 to 25 minutes. Remove the pan once the edges are golden and the center is set but soft.
  8. Cool completely in the pan. The cake will continue to firm up as it sits.
  9. Prepare the buttercream. Whip the softened butter and powdered sugar until light, airy, and ivory colored.
  10. Pipe the border. Add the heavy cream and vanilla to the frosting, then swirl it around the cooled perimeter.