In a large bowl, combine the melted butter, the brown sugar, and the granulated sugar. Whisk for 2-3 minutes. Add in the 2 eggs, the vanilla extract, vinegar, and food coloring, and whisk again until combined.
1/2 cup butter, 1/2 cup granulated sugar, 1/2 cup brown sugar, 2 eggs, 2 tsp vanilla, 2 tsp white vinegar, 1 tbsp red food coloring