Prepare the Chocolate Cake:
Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.
In a large mixing bowl, whisk together flour, sugar, cocoa powder, baking powder, baking soda, and salt.
Add milk, vegetable oil, eggs, and vanilla extract. Mix until smooth.
Slowly add boiling water, mixing until the batter is thin and well combined.
Divide the batter evenly between the prepared pans and bake for 30–35 minutes or until a toothpick inserted in the center comes out clean.
Let the cakes cool in the pans for 10 minutes, then transfer them to a wire rack to cool completely.
Make the Cherry Filling:
In a saucepan, combine cherries, sugar, cornstarch, water, and lemon juice.
Cook over medium heat, stirring constantly, until the mixture thickens and becomes glossy.
Remove from heat and let it cool completely before using.
Prepare the Whipped Cream:
In a chilled mixing bowl, beat heavy whipping cream, powdered sugar, and vanilla extract until stiff peaks form.
Assemble the Cake:
Place one cake layer on a serving plate. Spread half of the cherry filling evenly over the top.
Add a layer of whipped cream on top of the cherry filling.
Place the second cake layer on top and repeat with the remaining cherry filling and whipped cream.
Decorate the Cake:
Use the remaining whipped cream to frost the sides of the cake, if desired.
Garnish with chocolate shavings or curls for a decadent finishing touch.
Chill and Serve:
Refrigerate the cake for at least 1 hour before serving to allow the flavors to meld.