Serves 20
60 min
The World's Best Chocolate Oatmeal Cake
Recipe GLPR1de9160532757a
A decadent chocolate cake loaded with oatmeal, topped with chocolate chips and finished with a luxurious hot chocolate marshmallow frosting. This cake is moist, rich, and utterly irresistible with a glossy frosting that sets beautifully as it cools.
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Ingredients
6 tablespoons unsalted butter, softened
1 cup brown sugar, packed
1 cup white sugar
2 large eggs, lightly beaten
1¾ cups all-purpose flour
1 teaspoon baking soda
½ teaspoon salt
1½ tablespoons unsweetened cocoa powder
1 cup quick-cooking rolled oats
1¾ cups boiling water
12 oz semi-sweet chocolate chips, divided
6 tablespoons unsalted butter
1½ cups sugar
6 tablespoons whole milk
½ to ¾ cup mini marshmallows
Directions
Preheat your oven to 350°F (175°C). Grease or butter a 9x13-inch rectangular cake pan and set aside.
In a large bowl using an electric mixer, cream together the softened butter, brown sugar, and white sugar until light and fluffy, about 2-3 minutes.
Add the lightly beaten eggs to the butter-sugar mixture and beat well until fully incorporated.
In a separate bowl, whisk together the flour, baking soda, salt, and unsweetened cocoa powder. Add the dry ingredients to the wet ingredients and mix on low speed until just combined. The batter will be quite thick.
Pour the boiling water over the quick-cooking oats and let them stand for a few minutes until softened. Once the oats have absorbed the water and cooled slightly, add the oat mixture to the cake batter and mix well.
Fold in 6 ounces (half the bag) of the chocolate chips into the batter until evenly distributed.
Pour the batter into the prepared 9x13-inch pan and spread evenly. Sprinkle the remaining 6 ounces of chocolate chips evenly over the top of the cake.
Bake for 30-40 minutes until the surface springs back lightly when gently touched and the cake is fragrant. Do not overbake. The cake is done when a toothpick inserted in the center comes out with only a few moist crumbs.
Remove the cake from the oven and allow it to cool to room temperature on a wire rack.
While the cake cools, prepare the frosting. In a large saucepan, combine the butter, sugar, and milk over medium-low heat. Stir frequently until the butter melts, then bring to a boil. Boil for 30 seconds, then remove from heat.
Reduce the heat to low and add the chocolate chips and mini marshmallows to the hot mixture. Stir or whisk constantly until the frosting is completely smooth and glossy.
Pour the hot frosting immediately over the cooled cake, working quickly as the frosting will begin to set as it cools. Spread evenly with an offset spatula or the back of a spoon.
Allow the frosted cake to cool for 5 minutes before serving, or enjoy it warm if you prefer.
