A quick and easy White Chocolate Lava Mug Cake made in a Microwave. This healthy chocolate lava cake has a white chocolate center made with cashew butter and chocolate chips and is perfect for an instant gooey mug cake dessert. No oven or baking needed!

Stating a fact here: making a molten chocolate lava cake in a microwave is not as easy as I thought.

I’ve tried and test tested healthy mug cakes before and have that part nailed down – the light airy and fluffy texture. But getting a gooey molten chocolate center in a mug cake does not work the same unless you add a ton of the ‘bad ingredients’.

After a lot of experimenting, I found the key for this recipe: Cashew butter (or another nut/seed butter) stirred with a bit of coconut oil + chocolate chips.

So now the runny melty filling remains in place, instead of dropping to the bottom or drying out.

Ingredients for Chocolate Lava Cake with White Chocolate Center

This microwave white chocolate lava cake in a mug is made with whole wheat flour, cocoa powder and stevia, and filled with a molten white chocolate filling that uses cashew butter and stevia sweetened chocolate.

Here’s everything you need for this healthy microwave chocolate lava cake:

Whole Wheat Pastry Flour
Unsweetened Cocoa Powder or Cacao Powder would work too.
Baking Powder
Stevia Powder Sweetener – This keeps the chocolate mug cake sugar free and low calorie. Zero calorie Erythritol, Monk Fruit sweetener or even regular sugar would work.
Unsweetened Almond Milk – To keep it non-dairy and sugar free. Use a regular milk if you wish.
Egg – This is required for the light airy texture and prevents the cake from being too dense and rubbery.

For the White Molten Lava Cake filling:

Cashew Butter
Coconut Oil to stir in with the cashew butter to get the actual molten lava cake effect without having to bake
White Chocolate Chips or Chopped Chocolate. I would recommend Lily’s to keep it sugar free.

Can I substitute regular butter for cashew butter in this white chocolate lava cake recipe?

No, you need the cashew butter for the white molten lava cake effect, since there’s only a bit of actual white chocolate used. Regular butter would melt into the cake better and would not give you the gooey center when you cut it open.

An alternative for cashew butter would be another nut or seed butter like sunflower seed butter, macadamia butter, or almond butter.

How to make White Chocolate Lava Cake in the Microwave:

This White chocolate molten lava cake is really easy to make, and comes together in under 5 minutes! No oven preheating or baking time needed

Make your chocolate mug cake batter:

Mix all the dry ingredients – flour, cocoa powder, baking powder and stevia sweetener in a bowl.
Add the wet ingredients – milk and egg
Lightly whisk to combine – there will be small lumps, but that’s okay. Don’t over-mix the batter.

Make the Chocolate Cashew Butter Mug Cake Filling

Melt the coconut oil in a bowl
Add in the cashew butter and stir it until uniform

Assemble the chocolate lava cake and white chocolate center:

Grease a microwave safe mug or ramekin with coconut oil or cooking spray.
Pour ¾ batter into the mug
Spread the cashew butter mixture
Top with white chocolate chips or chopped chocolate
Pour remaining ¼ batter

How long does it take to microwave a cake?

For the perfect gooey chocolate mug cake, I recommend cooking in the microwave for exactly 45 seconds. The top of the cake should be just dry.

Microwave longer for 5 seconds at a time if needed.

Be careful here though, since microwaving for too long can make your mug cake overcooked and rubbery.

Tips for the perfect White Chocolate Molten Lava Cake Recipe

Use Whole Wheat Pastry Flour – Regular Whole Wheat would make it too dense and gummy.

Don’t over-mix the batter – This will also make a dense mug cake. Some small lumps in the batter are okay, and they go away or get cooked when microwaving.

Stir the cashew butter with melted coconut oil!
In case you’re hesitant to do this because of the extra fat, trust me and do it.
You need to follow this step for the molten white chocolate center in the chocolate lava cake, since the cashew butter will sink to the bottom otherwise.

Grease the inside of the ramekin or mug, and if possible, even dust it with more cocoa powder
This will allow the mug cake to come out easily when cooked

Why do mug cakes deflate?

If you see your regular mug cake deflate when cooled, it’s quite normal – this is because the steam rises excessively with the high heat and then escapes when you bring it out.

This recipe here should not deflate as much. I’ve tried it at least 5 times now, and I can tell you that it still retains shape and has the light airy texture of a mug cake, but with the gooey molten filling in the center.

If you still have issues with this one, it might be because you added too much baking powder, too much milk, or just over-mixed the batter. This could all cause the cake to rise up high, immediately sink when removed, and also give a dense texture overall.

Some more easy Microwave Mug Cake Recipes: