Chocolate Tunnel Cake

Ingredients

• CAKE
• 1 cup sugar
• 1 cup brown sugar
• 1 cup oil
• 2 eggs, lightly beaten
• 2 teaspoons vanilla
• 2 teaspoons baking soda
• 2 teaspoons baking powder
• 1/2 teaspoon salt
• 3/4 cup cocoa powder, sifted (I never sift)
• 3 cups flour
• 1 cup buttermilk
• 1 cup warm brewed coffee
• TUNNEL FILLING
• 1/4 cup sugar
• 8 ounces cream cheese, softened
• 1 teaspoon vanilla
• 1 egg
• 1 cup miniature chocolate chip
• GLAZE (OPTIONAL)
• 1 cup powdered sugar
• 3 unsweetened chocolate squares, melted and cooled
• 2 tablespoons unsalted butter
• hot water, to thin if needed