An eight-ounce mason jar holds two tablespoons of yellow cake mix and two tablespoons of angel food cake mix. Mixing these two specific batters gives you a fluffy cake texture right inside the jar without adding eggs or oil. A small splash of water sets the batter in motion.
You can assemble this dessert ahead of time for your pantry or gift it to a friend. A paper cupcake liner sits on top of the dry mix to keep the rainbow sprinkles separate until you are ready to heat it. When sweet cravings strike, the entire cake cooks in one minute.
Step-by-Step Instructions
1. Layer dry ingredients
Add two tablespoons of angel food cake mix and two tablespoons of yellow cake mix directly into an eight-ounce microwave-safe jar. Place a paper cupcake liner over the powder, fill the liner with one teaspoon of rainbow sprinkles, and seal the lid tightly.
2. Store dry mix
Keep the sealed jar in a cool pantry for up to three months. This keeps the dry cake layers fresh until you are ready to cook.
3. Add water batter
Remove the lid and lift out the cupcake liner containing the sprinkles. Pour two tablespoons plus one teaspoon of water into the dry mix and stir thoroughly, scraping along the bottom edges of the jar so no dry flour remains.
4. Start initial microwave
Microwave the jar uncovered on high power for 20 seconds. This initial burst starts setting the structure of the cake.
5. Fold in sprinkles
Scatter the reserved rainbow sprinkles into the warm batter. Stir very gently so the sprinkles distribute evenly without sinking straight to the bottom.
6. Finish cooking cake
Return the jar to the microwave and heat for another 40 seconds. The sponge will expand and set completely.
7. Garnish and serve
Spoon whipped cream on top of the warm cake and scatter extra sprinkles over the cream. Serve immediately while warm.
Tips & Tricks
- Measure the water precisely because an extra tablespoon will make the cake gummy.
- Eat the cake straight from the warm jar with a long spoon.
Variations
Chocolate Swirl
Add a teaspoon of Nutella to the dry mix step and swirl another teaspoon in when folding the sprinkles.
How to Store Birthday Cake In A Jar
Refrigerator
Store cooked leftovers covered in the refrigerator for up to 2 days.
Freezer
Freezing cooked cake in the jar is not recommended as the texture will degrade.
Reheating
Warm chilled leftovers in the microwave for 10 to 15 seconds until warm.
Frequently Asked Questions
Q: Can I use a regular mug instead of a glass jar?
Yes, any microwave-safe mug with an eight-ounce capacity works fine for cooking.
Q: Why do I need two different cake mixes?
Angel food cake mix contains egg whites and leavening that lift the cake with just water, while yellow cake mix adds traditional flavor.

Birthday Cake In A Jar – Quick Microwave Treat
Make a single-serve birthday cake in a jar using two cake mixes and sprinkles. Microwave for one minute for a fast gift or instant dessert.
Ingredients
Instructions
- 1Layer dry ingredients — Add two tablespoons of angel food cake mix and two tablespoons of yellow cake mix directly into an eight-ounce microwave-safe jar. Place a paper cupcake liner over the powder, fill the liner with one teaspoon of rainbow sprinkles, and seal the lid tightly.
- 2Store dry mix — Keep the sealed jar in a cool pantry for up to three months. This keeps the dry cake layers fresh until you are ready to cook.
- 3Add water batter — Remove the lid and lift out the cupcake liner containing the sprinkles. Pour two tablespoons plus one teaspoon of water into the dry mix and stir thoroughly, scraping along the bottom edges of the jar so no dry flour remains.
- 4Start initial microwave — Microwave the jar uncovered on high power for 20 seconds. This initial burst starts setting the structure of the cake.
- 5Fold in sprinkles — Scatter the reserved rainbow sprinkles into the warm batter. Stir very gently so the sprinkles distribute evenly without sinking straight to the bottom.
- 6Finish cooking cake — Return the jar to the microwave and heat for another 40 seconds. The sponge will expand and set completely.
- 7Garnish and serve — Spoon whipped cream on top of the warm cake and scatter extra sprinkles over the cream. Serve immediately while warm.




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