Prepare the Oven and Pan: Preheat your oven to 350°F (180°C). Grease a 9-inch springform pan and line the bottom with parchment paper.
Make the Cake Batter: In a mixing bowl, cream together the softened butter and sugar until light and fluffy. Add eggs one at a time, beating well after each addition. Mix in the vanilla extract.
1/2 cup unsalted butter, 2/3 cup granulated sugar, 2 large eggs, 1 tsp vanilla extract
In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add the dry ingredients to the butter mixture alternately with the milk, beginning and ending with the dry ingredients. Mix until just combined; avoid overmixing.
1 1/2 cups all-purpose flour, 2 tsp baking powder, 1/4 tsp salt, 1/2 cup milk
Assemble the Cake: Pour the batter into the prepared pan, spreading it evenly. Distribute the pitted cherries over the batter.
2 cups sour cherries
Prepare the Streusel Topping: In a bowl, combine flour and sugar. Add cold, cubed butter. Use your fingers or a pastry cutter to blend until the mixture resembles coarse crumbs. If using nuts, stir them into the streusel mixture.
1 cup all-purpose flour, 1/2 cup granulated sugar, 1/2 cup unsalted butter, 1/2 cup sliced almonds or chopped nuts
Add Streusel to the Cake: Sprinkle the streusel evenly over the cherries.
Bake: Bake in the preheated oven for 45-50 minutes, or until a toothpick inserted into the center comes out clean. If the top browns too quickly, cover loosely with aluminum foil.
Cool and Serve: Allow the cake to cool in the pan for about 15 minutes. Remove the sides of the springform pan. Serve warm or at room temperature.