Molten S’mores Mug Cake
Table of contents
There is something chaotic and beautiful about eating dessert out of a mug. Especially when it is gooey, chocolatey, marshmallow filled chaos like this molten s’mores mug cake.
This recipe started as a random 9:30 PM craving and quickly turned into a repeat offender. It is brownie meets graham cracker meets molten s’more, only it is high protein and does not require you to light anything on fire. The center stays soft and gooey, the chocolate melts just right, and the marshmallow gives you that classic pull apart s’mores moment with a spoon.
The microwave version is instant gratification. The oven version feels slower and cozier, like dessert you planned on purpose. Either way, this is best eaten warm, preferably while wearing fuzzy socks and standing in the kitchen.
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Why You’ll Love This Molten S’mores Mug Cake
• Ready in minutes
• Single serve and no leftovers
• Gooey marshmallow center
• Classic s’mores flavor without a campfire
• High protein and surprisingly filling
• Microwave or oven friendly
If you love s’mores but want a quick dessert without baking a whole pan, this mug cake is the answer.
What Makes This a True Molten S’mores Dessert
The secret is layering, not mixing.
The batter cooks around the marshmallow fluff or mini marshmallows, which melt into the center and create that signature molten s’mores texture. The chocolate chips add richness, while the graham cracker topping gives you that nostalgic crunch.
Letting the mug cake rest briefly after cooking helps the center stay gooey without turning runny.
Key Tips for the Best S’mores Mug Cake
Use a large mug or ramekin
This recipe rises while cooking. A 10 to 12 ounce mug helps prevent overflow.
Watch the microwave timing closely
Start with 45 to 50 seconds if your microwave runs hot. The center should look slightly underdone.
Do not skip the marshmallow
That molten center is what makes this a s’mores mug cake instead of a brownie.
Add toppings after cooking
Graham crackers stay crunchy when added at the end.
Oven method for extra cozy vibes
Baking gives firmer edges with a soft, molten center.
Ingredient Swaps & Variations
No almond flour -> Oat flour or all purpose flour work well
No protein powder -> Add more almond flour or skip for a classic dessert texture
No maple syrup -> Honey or brown sugar mixed with a splash of milk
No marshmallow fluff -> Use mini marshmallows or extra chocolate chips
No graham crackers -> Crushed cookies or granola give a similar crunch
This recipe is very forgiving and easy to customize based on what you have.
Storage & Reheating
his molten s’mores mug cake is best eaten fresh. If needed, cover and refrigerate for up to 1 day. Reheat in the microwave for 10 to 15 seconds until warm again.
If making ahead, store the graham cracker topping separately and sprinkle on just before eating.
Frequently Asked Questions
Yes. The microwave is the fastest option and works perfectly. Start with 45 to 50 seconds and adjust as needed.
Slightly undercook the mug cake and let it rest for one minute before eating. The center will stay soft and melty.
Yes. Bake at 350°F for 12 to 15 minutes until the edges are set and the center is still soft.
A 10 to 12 ounce microwave safe mug or a small ramekin works best.
Yes. You can replace it with more almond flour for a more traditional dessert texture.
Mini marshmallows or chocolate chips work well for a gooey center.
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Molten S’mores Mug Cake
Ingredients
- 2 tbsp almond flour
- 1 tbsp protein powder vanilla or chocolate
- 1 tbsp maple syrup
- 1 egg
- 1 tbsp milk
- 1/4 tsp baking powder
- Pinch of salt
- 1 tbsp mini chocolate chips
- 1 tbsp marshmallow fluff or mini marshmallows, for the molten center
- graham cracker crushed; optional, for topping
Instructions
- Mix everything except marshmallow fluff and graham cracker in a mug.
- Drop the fluff/marshmallows into the center.
- Microwave for 50-60 seconds.
- Top with graham cracker crumbs for that true s’mores vibe.
Oven Version:
- Preheat your oven to 350°F (175°C).
- Prepare the batter as above, but pour it into an oven-safe ramekin or small baking dish (6-8 oz size).
- Add marshmallow fluff or mini marshmallows to the center, without stirring.
- Bake for 12-15 minutes, until set around the edges with a soft, molten middle.
- Cool slightly, top with graham cracker crumbs, and dig in!
Notes
• Start with less microwave time and increase slowly to avoid overcooking.
• Let the mug cake rest for one minute before eating for best texture.
• Add graham crackers after cooking so they stay crunchy.
• Best eaten fresh, but can be refrigerated for up to one day and reheated gently.
