Ready to make a fun, colorful from-scratch funfetti cake? Skip the box mix (this time; you know I’m a fan more often than not) and make this homemade cake with the kids, for a church function or get-together, or just a snack cake to enjoy at home. No eggs or butter in the batter; the white vinegar + baking soda do all the work of making the cake rise to perfection.
Tools & Equipment
- Mixing bowl
- Measuring cups & spoons
- Whisk
- Spatula/bowl scraper
- 8×8 (square) baking dish
How to Make Funfetti Crazy Cake
Get everything out before you start to bake. If you have been following this blog for a while, you’ll see that I struggle with this concept personally, but it really does help the process go more smoothly.
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Prepare the pan and heat the oven. Preheat the oven to 350°F. Lightly grease a 9×9-inch baking pan with cooking spray or butter/flour and set aside. If you have an 8×8 or 11×7 (I call this my brownie pan), this will require less time to bake.
Stir or whisk the dry ingredients: In a large mixing bowl, whisk together the flour, sugar, baking soda, and salt until combined.

Make the wells (aka dents, nests or holes). Why wells? Well, (see what I did there) by keeping all the wet ingredients separate until ready to stir them together at the same time is what makes a crazy cake work. Using a spoon or clean hands, gently shuffle the dry ingredients to make a large dent in the center, and two smaller wells around it. They only serve to keep ingredients separate and nothing about them needs to be perfect. Measure and pour vegetable oil into the large hole, vinegar into one small hole, and the vanilla into the last hole.

Add the water and stir. Pour the cold water over everything and immediately stir just until you don’t see any more dry ingredients.

Rainbow time! Again, you don’t want to overmix here, so fold in gently.

Pour and bake. Pour in the batter, scraping the sides of the bowl to get every last bit into the pan. Bake at 350°F for 25–30 minutes. If you’re using a shallower pan than an 8×8, start checking at the 20-minute mark.


Cool and frost. You know the drill, and this is where patience is the hardest part. Let the cake come to room temp. If you want it frosted: Here’s my light cream cheese frosting that is not too heavy on the cream cheese flavor, or try my Blue Frosting colored with natural blue spirulina to go with the colorful theme, and it has no dyes or artificial gel colorings. Or if you want to go even lighter, here’s a stabilized whipped cream to try.

Tips
- No dilly-dallying. Once you get to the point where you have wells in your dry ingredients, you don’t want to wander off to check your socials. Stir together, add the sprinkles, then get it all into the oven fairly quickly. The chemical reaction of the wets is what makes this “crazy.”
- Once the sprinkles/jimmies are in the batter, just barely stir since the color will start to “bleed.” We want pretty spots, not streaks.
- This will still be tasty after three days kept covered, and is quite good eaten cold. If you are doing a prep bake, don’t frost yet; double wrap in cellophane tightly and freeze for up to three months. Thaw in the fridge for best results when it’s time to eat it.
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Funfetti Crazy Cake
Ingredients
- 1 1/2 cups all-purpose flour
- 1 cup granulated sugar
- 1 teaspoon baking soda
- 1/2 teaspoon salt
- 5 tablespoons vegetable oil
- 1 tablespoon white vinegar
- 1 teaspoon vanilla extract
- 1 cup cold tap water
- 1/4 cup rainbow sprinkles (jimmies) plus extra for decoration
- Frosting of choice
Instructions
- Preheat oven to 350°F. Grease and flour or spray a 9×9-inch baking pan; set aside. If using a shallower pan, it will require less bake time.
- In a large mixing bowl, whisk together the flour, sugar, baking soda, and salt.
- Make a large well (dent or hole) in the center of the dry ingredients and two small wells next to it.
- Into the large well: measure out the vegetable oil and pour in; add the vinegar into one small well, and the vanilla extract into the other. It's important to keep the wet ingredients separate until they're stirred into the batter at the same time.
- Moving quickly, add the water and stir the batter just until all ingredients are combined. You don't want to let it sit, since this is where the leavening action takes place.
- Fold in the sprinkles, but do not over-stir because they can "bleed" and the cake will have streaks.
- Pour the batter into the prepared baking pan. Bake at 350°F for 25-30 minutes, until a toothpick inserted into the center comes out clean. (Remember to check it sooner if you are using an 8×8 or 11×7.)
- Cool the cake completely to room temp, then frost with any frosting you like and add more sprinkles to the top.
Notes
The bottom line
We have a couple different crazy cakes on the site and this one is the most colorful by far! It’s an easy snack cake with a handful of rainbow sprinkles. (Don’t have sprinkles? Leave them out and you get a fine basic homemade vanilla cake.)
Want more cake recipes? Here you go!
- Lemon Crazy Cake
- Pumpkin Crazy Cake
- Apple Dapple Cake (one of the most popular on CookingChew.com)
- Italian “Hangover” Cake
- Ube Cake
- Heath Bar Poke Cake


