Ingredients:

  • 190g All-purpose flour
  • 200g Granulated sugar
  • 45g Unsweetened Dutch-process cocoa powder
  • 1 tsp Baking soda
  • 0.5 tsp Fine sea salt
  • 240ml Boiling water
  • 80ml Neutral oil (avocado or grapeseed)
  • 1 large egg, room temperature
  • 1 tsp Pure vanilla extract
  • 115g Unsalted butter, softened
  • 100g Marshmallow fluff
  • 60g Powdered sugar
  • 1 tbsp Heavy cream
  • 175g Semi-sweet chocolate chips
  • 2 tbsp Coconut oil

Instructions:

  1. Preheat your oven to 350°F (175°C) and line an 8x8-inch baking pan with parchment paper.
  2. Whisk the all-purpose flour, granulated sugar, baking soda, and sea salt in a large bowl.
  3. Bloom the cocoa by pouring 240ml boiling water over the cocoa powder in a heat-proof jug, whisking until smooth.
  4. Whisk the oil, egg, and vanilla into the cocoa mixture, then gently fold the wet ingredients into the dry ingredients until just combined.
  5. Pour the batter into the prepared pan and bake for 22–25 minutes until the center springs back. Let the cake cool completely.
  6. Prepare the filling by beating the softened butter, marshmallow fluff, powdered sugar, and heavy cream with an electric hand mixer until light and fluffy.
  7. Slice the cooled cake into 9 squares. Use a small paring knife or piping tip to core a small hole in the center of each square and pipe in the marshmallow filling.
  8. Melt the chocolate chips and coconut oil together in 30-second intervals in the microwave, stirring until glossy. Dip the top of each cake into the glaze and set on a wire rack to firm up.