Sourdough Chocolate Cake

Name: Sourdough Chocolate Cake
Prep time: 20 min
Cook time: 35 min
Total time: 55 min
Cuisine: American
Ingredients: 2 cups flour; 1/2 cup coconut oil; 1/2 cup sourdough starter (discard or active starter); 1 cup water; 2 large eggs; 2 cups granulated sugar; 1 teaspoon salt; 1 teaspoon finely ground coffee (optional); 2 teaspoons vanilla; 3/4 cup cocoa; 1 cups whole milk; 2 teaspoons baking soda; 1 cup salted butter (softened); 3 cups powdered sugar; 1/2 cup cocoa powder; 3-4 tablespoons heavy cream