Ingredients:

  • 2.5 cups all-purpose flour
  • 1 cup granulated sugar
  • 1 tbsp baking powder
  • 0.5 tsp salt
  • 0.75 cup unsalted butter, softened
  • 3 large eggs
  • 1 cup buttermilk
  • 1 tsp pure vanilla extract
  • 1 cup unsalted butter
  • 1.5 cups packed light brown sugar
  • 0.5 cup whole milk
  • 0.5 tsp salt
  • 1 tsp vanilla extract

Instructions:

  1. Beat the softened butter and sugar together until light and fluffy.
  2. Add eggs one at a time, beating well after each addition to ensure the batter doesn't break.
  3. Alternately add the flour mixture and buttermilk, starting and ending with the flour. Stir in the vanilla.
  4. Pour the batter into a greased 9x13 inch baking pan and bake at 350°F (175°C) until a toothpick inserted in the center comes out clean. Let it cool completely on a wire rack.
  5. In a heavy-bottomed saucepan, melt the butter over medium heat and stir in the brown sugar.
  6. Gradually pour in the milk. Bring the mixture to a gentle boil, then reduce to a simmer.
  7. Stir constantly for 5–8 minutes until the icing thickens and smells nutty and toasted.
  8. Remove from heat and stir in the salt and vanilla extract.
  9. While the icing is still warm, pour it evenly over the cooled cake.