Preheat your oven to 350°F (175°C). In a medium saucepan, melt 4 tablespoons of unsalted butter over medium heat. Once melted, stir in 1 cup of granulated sugar and cook until bubbling. Add 2 cups of pitted tart cherries and a splash of vanilla extract, mixing well. Pour this cherry mixture into a greased and lined 9-inch round cake pan.

In a large mixing bowl, sift together 1.5 cups of all-purpose flour, 2/3 cup of unsweetened cocoa powder, 1.25 cups of sugar, 1.5 teaspoons of baking powder, 1 teaspoon of baking soda, and 0.5 teaspoon of salt. In a separate bowl, whisk together 2 large eggs, 1 cup of buttermilk, 0.5 cup of vegetable oil, and 2 teaspoons of pure vanilla extract until fully combined. Gradually mix the wet ingredients into the dry ingredients until just combined.

Stir in 1 cup of boiling water into the batter until smooth. Ensure there are no dry flour pockets left.

Gently pour the prepared batter over the cherry topping in the cake pan, spreading it evenly. Take a moment to admire the contrasting colors before baking.

Bake the cake for 35-40 minutes or until a toothpick comes out clean. The edges will pull slightly away from the pan.

Allow the cake to cool in the pan for about 10 minutes. Run a knife around the edges and invert it onto a serving plate.