1-First Step: Preheat and Prepare Your Pan Start by preheating your oven to 350°F. While the oven heats up, grab a 9×13-inch baking pan. Grease the pan thoroughly with butter or cooking spray, and then dust it with a little flour. This step ensures that your cake releases easily after baking. If you prefer, you can line the pan with parchment paper for extra insurance.

2-Second Step: Create the Sour Milk Mixture In a small measuring cup, combine the 1 cup of milk with 1 tablespoon of fresh lemon juice. Stir gently and let it sit for about 5 minutes. You will notice the milk start to curdle and thicken slightly. This homemade buttermilk substitute adds a wonderful tenderness to the cake crumb and helps activate the baking soda for a good rise.

3-Third Step: Mix the Dry Ingredients In a large mixing bowl, whisk together the dry ingredients. Add the 1 ¾ cups of all-purpose flour, 1 ¾ cups of granulated sugar, ¾ cup of unsweetened cocoa powder, 2 teaspoons of baking soda, and 1 teaspoon of baking powder. Whisking these together ensures that the leavening agents are evenly distributed throughout the flour, which prevents any bitter spots in your finished cake.

4-Fourth Step: Combine Wet and Dry Ingredients Add the wet ingredients to the bowl with the dry ingredients. Crack in the 2 eggs, pour in the 1 cup of cooled brewed coffee, add the soured milk mixture you made earlier, the ½ cup of vegetable oil, and the ½ teaspoon of vanilla extract. Using an electric mixer on medium speed, beat the batter for about 2 minutes. It is important not to overmix, but 2 minutes is just right to develop the structure and incorporate air.

5-Fifth Step: Bake the Cake Pour the smooth batter into your prepared 9×13-inch pan. Use a spatula to spread it evenly. Place the pan in the preheated oven and bake for 30 to 40 minutes. Every oven is different, so start checking at the 30-minute mark. Insert a wooden toothpick into the center of the cake. If it comes out clean or with just a few moist crumbs, the cake is done.

6-Sixth Step: Poke and Soak Remove the cake from the oven and let it cool in the pan for about 15 minutes. It should still be slightly warm but not hot. Take the handle of a wooden spoon and poke holes all over the top of the cake. Space the holes about an inch apart, making sure they go deep into the cake but do not hit the bottom of the pan. Slowly pour the 14 ounces of sweetened condensed milk over the cake, followed by three-quarters of the 1 cup of caramel sauce. Let this mixture seep down into the holes.

7-Final Step: Chill and Top Cover the pan with plastic wrap or aluminum foil and place it in the refrigerator. Let it chill for at least 4 hours, though overnight is even better. This resting period allows the flavors to meld and the cake to become incredibly moist. When you are ready to serve, spread the 8 ounces of whipped topping or 3 cups of whipped cream over the surface. Drizzle with the remaining caramel sauce and chocolate sauce, then sprinkle generously with chopped chocolate.