Make a Killer Crumb Cake With Boxed Muffin Mix

Boxed muffin mixes are convenient for baking up a dozen hand-held quick breads, but that’s not all they can do. The pre-packaged mixture contains flour, sugar, flavorings, and a leavening agent, ingredients that are consistent with a number of other cake-like desserts. In fact, with a couple of simple adjustments, you can transform a basic box of muffin mix into a decadent crumb cake, as the dry mixture can be manipulated to become both the cake and the crumb.

There’s nothing wrong with a muffin, but having a whole crumb cake is better for everyone. First and foremost, you must create the perfect crumb layer. Crisp, but not hard. Soft, but not mushy. I poured out my box mix (which was the 18.25-ounce Krusteaz chocolate chunk muffin mix) into a large mixing bowl and scooped one cup of the mix out into a separate, smaller bowl for the crumble. I blended in brown sugar and cinnamon, then added melted butter to the smaller bowl. After some stirring and pressing, the crumb mixture became well-moistened with butter. (It should be clumpy, but not sodden with butter.)

Crumble topping before stirring.Photo: Allie Chanthorn Reinmann

The directions on a typical boxed muffin mix includes the addition of water, oil, and eggs. The batter will be thick, and the resulting quick bread sturdy and slightly dry. To achieve a moist, cake-like batter with the same dry ingredients, I decided to loosen up the batter and take out an egg, so the final crumb wouldn’t be as dry as a muffin’s. Luckily, this made my life easy. To make a looser batter, I used a higher ratio of wet ingredients, and since I already took out a cup of the dry ingredients for the crumb, this meant I could keep the liquids nearly the same as directed on the box.

The box asks for a 1/2 cup of both water and oil. I measured them out on the scant-side (so just erring on the light end of the measurement), and I subtracted one egg from what the box directed. The only change I would make in the future would be to reduce the oil measurement a tad more than I did, to 1/3 cup instead of 1/2 cup. This would keep the cake spongy, but lighten it up.

Mix the water, oil, and eggs into the box mix until smooth. Pour it into a buttered, parchment-lined cake pan, or casserole dish. The batter should be flowing, but not watery. Using your hands, break apart the crumb mixture and drop it all over the surface of the batter, until it’s evenly covered with little crumble bits. Bake in a 350°F oven for 45 minutes, or until the center springs back when gently pressed.

Photo: Allie Chanthorn Reinmann

Allow the cake to cool for at least 20 minutes before turning it out of the pan, so the topping can set. Flip it upside down onto a plate, place another plate over the bottom and flip it again so the crumb-side is facing up. Dust with a load of powdered sugar and serve. The crumble is crusty but soft, with a warm aroma of cinnamon, and the cake is moist and delicate–a far cry from a dry, dense muffin.

Although my muffin mix was studded with chocolate chunks, this boxed-muffin-mix-turned-crumb-cake would be stellar using a banana muffin, blueberry, or plain mix. Keep in mind that the following recipe uses an 18.25-ounce box of muffin mix, so if your mix is a different weight, you’ll need to adjust some measurements. Well-covered, this crumb cake keeps at room temperature for up to five days, or in the fridge for a week.

Crumb Cake from a Muffin Box Mix

Crumb topping ingredients:

Cake batter ingredients:

Preheat the oven to 350°F. Butter a 9-inch cake pan and fit a parchment paper circle into the bottom of the pan.

Pour the entire box of muffin dry mixture into a large bowl. Scoop out one cup of the dry mixture and place it into a smaller bowl for the crumble. Blend the brown sugar and cinnamon with the small amount of muffin mix. Pour in the melted butter. Stir and press it all together until well-combined and clumpy. Set aside.

Prepare the cake batter in the large bowl with the remaining boxed muffin dry mixture. Add the water, oil, and 2 eggs. Mix together until well combined. Pour the batter into the cake pan and smooth it out. Use your fingers to break apart the crumble while you sprinkle it over the surface of the batter. Make the layer of crumb bits as even as possible. No need to press the crumbs into the surface.

Bake at 350°F for 45 minutes, or until the center springs back when gently pressed. Cool completely before flipping it out of the pan.