This 3-ingredient slow cooker confetti cake is my go-to when I want a fun, colorful dessert that basically takes care of itself while I handle the rest of the day. It bakes up into a fluffy white sponge right in the slow cooker, with little rainbow flecks of sprinkles running through every slice. There’s no fancy origin story here—just a busy Midwestern mom discovering that a boxed cake mix, a couple of pantry staples, and a slow cooker can turn into a warm, steamy “celebration in a bowl” with almost no effort.
Serve this confetti cake warm right from the slow cooker, scooping it into bowls like a cozy dessert casserole. It pairs perfectly with a scoop of vanilla ice cream, a dollop of whipped topping, or even a drizzle of chocolate or caramel syrup if you want to dress it up a bit. For kids, I like to set out a small bowl of extra rainbow sprinkles so they can decorate their own bowls. A cup of coffee or hot cocoa for the grown-ups alongside this soft, steamy cake makes it feel like a little weeknight party without any fuss.
3-Ingredient Slow Cooker Confetti Cake
Servings: 8-10
Ingredients
1 box (15.25 oz) white cake mix
1 1/4 cups whole milk (or 2% milk)
1/2 cup rainbow sprinkles (jimmies-style, not nonpareils)
Directions
Spray the inside of a 4- to 6-quart slow cooker generously with nonstick cooking spray, or lightly grease it with butter or oil. This helps the soft cake release easily and keeps the edges from sticking.
In a medium mixing bowl, whisk together the dry white cake mix and the milk until the batter is mostly smooth. A few small lumps are fine; just make sure there are no big dry pockets of mix at the bottom of the bowl.
Gently fold in the rainbow sprinkles with a spatula, stirring just until they are evenly distributed. Try not to overmix so the colors don’t bleed too much into the batter—you want those pretty little specks throughout the white cake.
Pour the batter into the prepared slow cooker and smooth the top with the back of a spoon or a spatula so it cooks evenly.
Cover the slow cooker with its lid. If your lid tends to drip condensation, you can lay a clean kitchen towel or a couple of paper towels over the top of the crock before putting the lid on, to catch excess moisture and keep the top of the cake fluffy. Just make sure the towel edges are away from the heating element.
Cook on LOW for 2 1/2 to 3 hours, or until the cake is puffed, the edges are set, and the center springs back lightly when touched. You can also test with a toothpick inserted into the center; it should come out mostly clean with just a few moist crumbs.
Once done, turn off the slow cooker and let the cake sit, covered, for about 10 minutes. This resting time lets the steam settle and keeps the crumb tender and moist.
Scoop the warm confetti cake directly from the slow cooker into bowls. Serve as-is for a simple, cozy treat, or top with ice cream or whipped topping if you’d like to make it extra festive.
Variations & Tips
For extra richness, you can swap half of the milk for heavy cream, which makes the cake even more velvety and indulgent. If your family likes things less sweet, use only 1/3 cup of sprinkles so the cake has just a light confetti look. For kids who are picky about colors, try using only one or two colors of sprinkles (like all blue or all pink) to match a party theme. This recipe works well with other flavors of boxed mix, too—yellow cake mix will give you a slightly more buttery, custardy vibe, while a funfetti mix doubles up on the sprinkles without changing the process. If you need to make it dairy-light, you can use unsweetened almond milk or oat milk in place of dairy milk; just know the texture will be a touch less rich but still very soft and moist. To keep the top from getting soggy, don’t skip the towel trick if your slow cooker tends to collect a lot of condensation. Leftover cake reheats nicely: scoop into a microwave-safe bowl and warm for 15–20 seconds until just steamy again. For a make-ahead party dessert, you can stir the batter together earlier in the day, refrigerate it in the mixing bowl, then pour into the slow cooker and start cooking about 3 hours before you want to serve, so dessert is warm and ready right when everyone is looking for something sweet.