My easy to make Microwave sponge cake bakes in under 8 minutes, is egg-free, and stays soft for 4 days! Celebrate anytime with this quick bake which has amazing flavour and texture.

Microwave Sponge Cake (Egg-free, Stays Soft for 3 days)

Name: Microwave Sponge Cake (Egg-free, Stays Soft for 3 days)
Prep time: 10 min
Cook time: 8 min
Total time: 18 min
Ingredients: 6 Tablespoons butter (softened); ½ cup sugar (see note 1); ¼ cup plain yogurt (see note 2); 1 cup full-fat milk; 1 ⅓ cups all-purpose flour OR cake flour; 2 teaspoons baking powder; 1 teaspoon vanilla extract

If you are a fan of quick bakes then you are going to love this Microwave sponge recipe. Super easy to make, and requires no special equipment or ingredients. All the ingredients are mixed in one bowl, baked, and frosted to your preference.

This cake is so soft, fluffy, and light and has such great flavour, nobody will believe that it was baked in the microwave. It makes the perfect celebration cake or anytime treats.

So next time, you rushed for time, just don't want to turn on your oven,

or need a quick treat, give this recipe a try. I know that you will love it too.

Just a note on a few ingredients and substitutes if needed

While the full recipe is written below, this is the section to read if you’re wondering about ingredient substitutions or how these ingredients work in the recipe.

Butter: This should be softened to room temperature so that it incorporates well with the sugar and overmixing is avoided.

Sugar: Use castor or white granulated sugar

Plain unflavored yogurt: Plain unflavoured yogurt is used in this recipe. If you do not have yogurt, then you can substitute it by adding 2 Tablespoons lemon juice or vinegar to 1 cup of milk. Set aside for 5 minutes before
using in the recipe.

Milk: It is best to use a full-fat mill for this bake.

Flour: Use either cake, plain, or all-purpose flour.

Baking Powder: This helps the cake to rise and give it that fluffy texture. Ensure that the baking powder is fresh and not past the expiry date.

Flavourings: I used vanilla extract. You can experiment with other flavourings and extracts like caramel or Strawberry

How to Make a Microwave sponge cake

While the video and the full printable recipe is written below, this is the process with step-by-step pictures to guide you.

Use a whisk or handheld beater to cream the butter. Add the sugar and vanilla extract and beat until well incorporated.
Pour in the yogurt and mix to combine.

Sift in the flour and baking powder and mix until just combined.

Add the milk and use a whisk or handheld beater to beat for l minute.

Pour the mixture into a microwave-safe dish lined with parchment paper. Bake in the microwave for between 6 to 8 minutes or the high power setting.

Check if the cake is baked after 6 minutes by inserting a toothpick in the centre. The cake should be baked if the toothpick comes out clean.

If after 6 minutes the cake has not finished baking, continue to bake it until done.

Keep in mind that the cooking time is going to vary depending on your microwave and the container you are using.

After baking leave the cake to cool in its container for 10 minutes. Then gently remove it from the container onto a plate. Cool completely before decorating with a frosting of your choice.

Frequently asked questions and tips.

Which cake pan is the best to use?

The container or pan used must be microwave safe. Keep in mind that the type of container used can affect the baking time and sometimes the texture of the cake. For example, I find that baking in a silicone container creates a denser bake compared to a glass container which creates a more fluffy texture.
Never use regular metal oven pans for any of your microwave baking.
Use only microwave-safe glass, silicone, plastic or ceramic containers.
It is preferable to use a rounded container for this cake as it cooks more evenly around the edges.

How do you know when the cake is baked

Microwave cakes bake very quickly, here are a few guidelines to have an idea of when it has baked.

Check if the cake is baked by inserting a toothpick or thin metal skewer into the middle of the cake. If there is batter clinging to the toothpick, put the cake back into the microwave and bake at 1-minute increments until baked.
The cake will be firm to the touch and will pull away from the sides of the pan when baked.

Helpful tips when baking cakes in the microwave

When using a regular microwave at full power to make a cake, cook for 8-10 minutes. Stop every 4 minutes and check your bake by using a toothpick to pierce the cake. if the toothpick comes out clean, your cake’s done. It’s also important to stop and check because timing can differ slightly depending on the microwave.
The baking time in my recipe is based on my 1000 watt microwave. This means that your baking time will vary by either a few minutes more or less depending on your microwave.
Do not overbake. Keep in mind that the cake continues to bake for at least another 2 minutes after it has been removed from the microwave.
The container or pan used must be microwave safe. Keep in mind that the type of container used can affect the baking time and sometimes the texture of the cake. For example, I find that baking in a silicone container creates a denser bake compared to a glass container which creates a more fluffy texture.

Toppings and frosting ideas

These can be as simple or elaborate as you like. Depending on the occasion or your mood (mine is always for chocolate 🙂 have fun with the topping. Here are the best toppings I have used in my recipes if you would like to give it a try:

Use your favourite frosting to decorate the cake. It can be as simple as a dusting of powdered sugar or as elaborate topped with a rich buttercream frosting which I used on my recipe for condensed milk lemon cake

Top with a simple dusting of powdered sugar
Frost with piped or spread with my favourite chocolate buttercream
Try my delicious stabilized 3 ingredient whipped cream frosting (without gelatin) and top with seasonal fruit
Cover with a chocolate ganache.