Black Raspberry Sheet Cake for 16

Instructions:

1. Combine black raspberries, 1/4 cup sugar, and lemon juice in a saucepan over medium heat. Simmer for 8–10 minutes until the berries break down and the liquid thickens into a syrupy consistency.
2. Press the berry mixture through a fine-mesh strainer to remove seeds, leaving a smooth purple reduction. Set aside to cool.
3. Preheat oven to 350°F (175°C) and grease a 13x9 inch sheet pan.
4. Cream the softened butter (170g) and 2 cups of sugar until pale and fluffy (about 3 minutes).
5. Beat in the eggs one at a time, followed by the vanilla extract.
6. Sift together flour, baking powder, and salt. Alternately add the dry ingredients and milk to the butter mixture, starting and ending with the flour, mixing until just combined.
7. Gently swirl 3 tablespoons of the cooled berry reduction into the batter to create a marbled effect.
8. Spread the batter evenly into the prepared pan and bake for 30–35 minutes.
9. Prepare the frosting by beating 1 cup of softened butter with powdered sugar, heavy cream, vanilla extract, and a pinch of salt until creamy.
10. Allow the cake to cool until barely warm to the touch, then spread the frosting evenly over the top.