I made delightfully festive cake bars with Halloween Oreos and colorful sprinkles that hide a secret ingredient, perfect for my Kid Friendly Halloween Desserts roundup.

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I love finding shortcuts that still feel a little wild, and these Easy Halloween Oreo Cake Bars totally fit that bill. Using a box of white or yellow cake mix and a package of Halloween Oreos makes something that looks like it took hours but doesnt.

People always ask if I bought them at a bakery even though theyre thrown together, they travel well and disappear fast. Perfect for Kid Friendly Halloween Desserts when you need a quick showstopper that feels special without being fussy.

I promise they look fancier than the three minutes they actually take to assemble.

Ingredients

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Cake mix: mostly refined carbs, lots of sugar, gives soft sweet base, quick and easy.
Eggs: add protein, bind ingredients, give moisture and rise, sometimes they make it richer.
Vegetable oil: pure fat for moist crumb, neutral flavor, not the healthiest choice but works.
Vanilla extract: a little goes far, adds warm sweet aroma and depth to flavor.
Halloween Oreos: crushed cookies add chocolate cream pockets, crunchy texture, totes sugary and fun.
Sprinkles: little sugar bits for color and crunch, pure sweetness, very decorative but empty calories.

Ingredient Quantities

1 (15.25 ounce) box white or yellow cake mix

3 large eggs

1 cup water

1/2 cup vegetable oil

1 teaspoon vanilla extract optional I usually add it

1 (14 to 15 ounce) package Halloween Oreos about 36 cookies

1/2 cup Halloween colored sprinkles plus more for topping

Nonstick cooking spray or softened butter for the baking pan

How to Make this

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1. Preheat oven to 350 F and grease a 9×13 inch baking pan with nonstick spray or softened butter so the bars don’t stick.

2. Roughly chop or crush the Halloween Oreos into bite size pieces. You can pulse them a few times in a food processor or put them in a zip bag and smash with a rolling pin, don’t pulverize them into dust.

3. In a large bowl whisk together the cake mix, 3 large eggs, 1 cup water, 1/2 cup vegetable oil and 1 teaspoon vanilla extract (optional but I usually add it) until smooth and no big dry streaks remain.

4. Fold the chopped Oreos and 1/2 cup Halloween colored sprinkles into the batter with a spatula, mixing just enough to distribute them evenly.

5. Scrape the batter into the prepared pan and spread it out evenly, smoothing the top with the back of a spoon or offset spatula.

6. Sprinkle a few extra crushed Oreos and more colored sprinkles on top for a festive finish, it makes them look way better.

7. Bake in the preheated oven for about 25 to 30 minutes. Start checking at 22 minutes since oven temps vary; a toothpick inserted in the center should come out with a few moist crumbs but not raw batter because of the cookie bits.

8. Let the bars cool in the pan on a wire rack for at least 15 to 20 minutes before slicing, or cool completely for cleaner squares. If you try to cut them too hot they’ll fall apart.

9. Use a sharp knife wiped between cuts or a bench scraper to get neat bars. Store leftovers in an airtight container at room temp for 2 to 3 days or refrigerate if your kitchen is warm.

10. Quick tips: room temperature eggs mix smoother, dont overmix the batter, and if you want fudgier bars bake a couple minutes less.

Equipment Needed

1. Oven (preheat to 350 F)
2. 9×13 inch baking pan, greased with nonstick spray or softened butter
3. Large mixing bowl
4. Whisk
5. Rubber spatula (for folding) and a regular spoon (for smoothing)
6. Food processor to pulse Oreos, or a heavy zip-top bag plus rolling pin to smash them
7. Measuring cups and measuring spoons
8. Offset spatula or the back of a spoon for evenly spreading batter
9. Sharp knife (wipe between cuts) or bench scraper for neat bars
10. Wire cooling rack (and toothpicks to test doneness)

FAQ

Q: What pan size, temp and bake time do I use?

Use a greased 9×13 inch pan, oven at 350°F. Bake about 25 to 30 minutes, check with a toothpick – a few moist crumbs is good. If you added extra Oreos it might need a few more minutes. Let cool before slicing.

Q: Can I swap ingredients or use a different cake mix?

Yep. White or yellow both work great, you can try chocolate but flavor changes. Oil can be swapped for melted butter, applesauce cuts fat but makes it denser, and flax eggs can work but texture will be different.

Q: Do I mix the Oreos into the batter or layer them?

Either way works. Toss chopped Oreos into the batter for even distribution, or press whole/halved Oreos into the batter for big cookie pockets. Chopping gives more even bites, layering looks fancier.

Q: How do I get clean bars when cutting?

Cool completely, then chill 20 to 30 minutes for neater cuts. Use a sharp knife wiped clean between cuts or dip the blade in hot water and dry it, you'll get pretty squares.

Q: How should I store or freeze them?

Store in an airtight container at room temp 3 to 4 days, refrigerate up to a week. Freeze wrapped in foil and plastic up to 3 months, thaw in the fridge or at room temp.

Q: Can I use regular Oreos or other cookies and add sprinkles?

Yes, regular Oreos are fine, or try flavored ones. Sprinkles can go in batter but they might bleed color, so I like to press sprinkles on top before baking or sprinkle on while the bars are still slightly warm.

Easy Halloween Oreo Cake Bars Recipe Substitutions and Variations

Eggs: swap each egg with 1 tbsp ground flax + 3 tbsp water (mix and let sit 5 minutes) for a vegan option, or use 1/4 cup unsweetened applesauce per egg if you want less fat; it may be a bit denser but still moist.
Vegetable oil: use the same amount of melted butter for richer flavor, or swap 1:1 with canola or light olive oil; you can also use 1:1 unsweetened applesauce to cut fat, though bars will be cakier.
Cake mix: use a 1:1 gluten free boxed cake mix if you need GF, or choose chocolate or funfetti mix instead for a flavor twist—just keep the same wet-ingredient amounts.
Halloween Oreos: about 36 regular Oreos or any chocolate sandwich cookies work fine, or use golden Oreos for a lighter look; you can also sub roughly chopped chocolate chip cookies for a different texture.

Pro Tips

1. Break the Oreos into a mix of sizes so you get big cookie pockets and little crumbs for even flavor. Dont pulverize them into dust or the bars will lose that chunky texture.

2. Use room temp eggs and mix just until the dry streaks are gone. Overmixing makes the bars tough, so fold in the cookies and sprinkles gently.

3. Watch your oven, every oven bakes different. Start checking a few minutes earlier than you think, rotate the pan halfway if your oven runs hot, and pull the bars when a toothpick has moist crumbs for a fudgier center.

4. Let the pan cool well before slicing and line the pan with parchment next time for clean lifts. Wipe your knife between cuts or warm the blade under hot water and dry it for neater squares.

Easy Halloween Oreo Cake Bars Recipe

Recipe by Tina Bueller

0.0 from 0 votes

I made delightfully festive cake bars with Halloween Oreos and colorful sprinkles that hide a secret ingredient, perfect for my Kid Friendly Halloween Desserts roundup.

Servings

servings

Calories

440

kcal

Equipment: 1. Oven (preheat to 350 F)
2. 9×13 inch baking pan, greased with nonstick spray or softened butter
3. Large mixing bowl
4. Whisk
5. Rubber spatula (for folding) and a regular spoon (for smoothing)
6. Food processor to pulse Oreos, or a heavy zip-top bag plus rolling pin to smash them
7. Measuring cups and measuring spoons
8. Offset spatula or the back of a spoon for evenly spreading batter
9. Sharp knife (wipe between cuts) or bench scraper for neat bars
10. Wire cooling rack (and toothpicks to test doneness)

Ingredients

1 (15.25 ounce) box white or yellow cake mix
3 large eggs
1 cup water
1/2 cup vegetable oil
1 teaspoon vanilla extract optional I usually add it
1 (14 to 15 ounce) package Halloween Oreos about 36 cookies
1/2 cup Halloween colored sprinkles plus more for topping
Nonstick cooking spray or softened butter for the baking pan

Directions

Preheat oven to 350 F and grease a 9×13 inch baking pan with nonstick spray or softened butter so the bars don't stick.
Roughly chop or crush the Halloween Oreos into bite size pieces. You can pulse them a few times in a food processor or put them in a zip bag and smash with a rolling pin, don't pulverize them into dust.
In a large bowl whisk together the cake mix, 3 large eggs, 1 cup water, 1/2 cup vegetable oil and 1 teaspoon vanilla extract (optional but I usually add it) until smooth and no big dry streaks remain.
Fold the chopped Oreos and 1/2 cup Halloween colored sprinkles into the batter with a spatula, mixing just enough to distribute them evenly.
Scrape the batter into the prepared pan and spread it out evenly, smoothing the top with the back of a spoon or offset spatula.
Sprinkle a few extra crushed Oreos and more colored sprinkles on top for a festive finish, it makes them look way better.
Bake in the preheated oven for about 25 to 30 minutes. Start checking at 22 minutes since oven temps vary; a toothpick inserted in the center should come out with a few moist crumbs but not raw batter because of the cookie bits.
Let the bars cool in the pan on a wire rack for at least 15 to 20 minutes before slicing, or cool completely for cleaner squares. If you try to cut them too hot they'll fall apart.
Use a sharp knife wiped between cuts or a bench scraper to get neat bars. Store leftovers in an airtight container at room temp for 2 to 3 days or refrigerate if your kitchen is warm.
Quick tips: room temperature eggs mix smoother, dont overmix the batter, and if you want fudgier bars bake a couple minutes less.

Notes

Below you’ll find my best estimate of this recipe’s nutrition facts. Treat the numbers as a guide rather than a rule—great food should nourish both body and spirit. Figures are approximate, and the website owner assumes no liability for any inaccuracies in this recipe.