Decadent Low-Carb Chocolate Peanut Butter Mug Cake

Okay, confession time. The other night, it was late, everyone else was asleep, and I had the most intense craving for something rich, chocolaty, and peanut buttery. You know the kind! I didn’t want to bake a whole cake or make a huge mess. I just needed dessert, like, now. After a bit of frantic kitchen experimenting over the years, tweaking things here and there, this Rich Chocolate Peanut Butter Mug Cake was born, and honestly? It’s become my emergency dessert go-to.

If you ever get those sudden cravings, need a super quick low-carb treat, or just want a perfectly portioned dessert without leftovers tempting you for days, you need this recipe in your life. It’s ridiculously fast and hits all the right decadent notes.

Why This Mug Cake Recipe Just Works

• Speed Demon: Seriously, you can whip the batter up in about 5-6 minutes. Bake time is under 20 minutes, or you can even zap it in the microwave if you’re really in a hurry!
• Dream Team Flavors: Chocolate and peanut butter – need I say more? It’s that classic combo we all adore, packed into a warm, gooey little cake.
• Low-Carb Magic: Using almond flour and a low-carb sweetener keeps it friendly for keto and low-sugar lifestyles, but trust me, you won’t feel like you’re missing out on anything.

Gather Your Goodies (Ingredient Breakdown)

Here’s what you’ll need to make these little cups of heaven:

• 15 tablespoons Almond Flour: Finely ground works best for a smooth texture. (That’s about ¾ cup plus 3 tablespoons).
• 6 tablespoons Granulated Low-Carb Sweetener: Use your favorite erythritol blend like Swerve. Feel free to adjust slightly based on your sweetness preference!
• 1 ½ teaspoons Baking Powder: Gives our little cake some lift.
• 3 ½ tablespoons Unsweetened Cocoa Powder: For that deep chocolate flavor. Don’t use sweetened cocoa!
• ½ teaspoon Instant Espresso Powder: This is my secret weapon! It deepens the chocolate flavor without tasting like coffee. Optional, but highly recommended.
• 3 large Eggs: These bind everything together and add richness. Bringing them to room temp first is great if you remember!
• 1 ½ tablespoons Smooth Peanut Butter: Make sure it’s unsweetened and no sugar added to keep it low-carb. Creamy works best here.
• 6 tablespoons Unsalted Butter, melted: For moisture and flavor. You can sub melted coconut oil for a dairy-free version!
• ¾ teaspoon Vanilla Extract: Because vanilla makes everything better.
• 1 ½ tablespoons Sugar-Free Chocolate Chips: Use your favorite brand (like Lily’s). Sprinkle them on top!
• Optional Pinch of Salt: About 1/8 tsp, especially if your butter and peanut butter are unsalted. It just balances the sweetness.

Let’s Make Some Magic (Step-by-Step)

1. Get Ready: Fire up your oven to 340°F (170°C). Find four cute oven-safe ramekins or mugs and give them a little grease so nothing sticks.
2. Dry Stuff: Grab a medium bowl. Dump in the almond flour, sweetener, baking powder, cocoa powder, and that magic espresso powder (plus the salt, if you’re using it). Whisk it all together until it’s nicely combined and lump-free.
3. Egg Power: In a separate, smaller bowl, whisk those eggs like you mean it! Get them pale yellow and a bit fluffy – this adds airiness.
4. Wet Meets Dry: Pour the whisked eggs, melted butter (or coconut oil), peanut butter, and vanilla right into the bowl with the dry ingredients.
5. Mix Gently: Using a spatula or spoon, carefully fold everything together. Stop mixing as soon as it’s combined – overmixing can make your cake tough!
6. Fill ’em Up: Spoon the batter evenly into your prepared ramekins or mugs. Sprinkle those lovely sugar-free chocolate chips over the top.
7. Bake Time: Pop them into the hot oven. Let them bake for about 17 to 21 minutes. They should look set around the edges. A toothpick poked near the center should come out mostly clean (or with moist crumbs if you like it a bit gooey).
8. Patience, Grasshopper: Carefully take them out of the oven (they’re hot!). Let them cool in the ramekins for at least 3-5 minutes. This helps them firm up a bit before you dig in.

Pro Tips for Perfect Mug Cakes

• Swap it Out: No butter? Melted coconut oil works great. Want a different nutty flavor? Try unsweetened almond butter (check carb counts if you’re strict keto).
• Avoid the Dry-Out: Keep a close eye during the last few minutes of baking. Almond flour bakes fast, and overbaking is the enemy of a moist mug cake!
• Storage Smarts: Honestly, these are best eaten warm and fresh. If you do have leftovers, cover them tightly and store them in the fridge for maybe a day. Gently reheat in the microwave, but the texture is best right after baking.
• Microwave Warrior: If using the microwave (70-100 seconds), start checking on the earlier side. Microwaves cook fast and unevenly sometimes!

Serving Suggestions & Perfect Pairings

These little cakes are amazing just as they are, warm from the oven. But if you want to go extra…

• Top with a scoop of low-carb vanilla or peanut butter ice cream.
• Add a dollop of unsweetened whipped cream.
• Drizzle with a little extra melted peanut butter (or sugar-free chocolate sauce!).
• A few fresh raspberries on the side add a lovely contrast.
• Perfect alongside a cup of coffee, tea, or a cold glass of unsweetened almond milk.

They’re fantastic for a quick weeknight treat, a cozy dessert on movie night, or anytime you just need one perfect serving of chocolate-peanut butter goodness.

Rich Chocolate Peanut Butter Mug Cake

A decadent, single-serving style dessert perfect for satisfying chocolate and peanut butter cravings quickly. This low-carb treat bakes up rich and moist in individual portions.

Print Recipe Pin Recipe

Prep Time 6 minutes mins

Cook Time 18 minutes mins

Total Time 24 minutes mins

Ingredients

  

• 15 tablespoons Almond Flour equiv. to ¾ cup + 3 Tbsp
• 6 tablespoons Granulated Low-Carb Sweetener e.g., Erythritol-based like Swerve
• 1 ½ teaspoons Baking Powder
• 3 ½ tablespoons Unsweetened Cocoa Powder
• ½ teaspoon Instant Espresso Powder
• 3 large Eggs
• 1 ½ tablespoons Smooth Peanut Butter unsweetened, no sugar added
• 6 tablespoons Unsalted Butter melted (or Coconut Oil for dairy-free)
• ¾ teaspoon Vanilla Extract
• 1 ½ tablespoons Sugar-Free Chocolate Chips e.g., Lily's brand
• Optional: Pinch of Salt approx 1/8 tsp, especially if using unsalted butter/peanut butter

Instructions

 

• Prepare Oven & Dishes: Set your oven to preheat at 340°F (170°C / Gas Mark 3). Lightly grease four individual ramekins or oven-safe mugs.
• Combine Dry Components: In a medium bowl, thoroughly mix the almond flour, sweetener, baking powder, cocoa powder, and instant espresso powder using a fork or whisk until uniform and free of clumps. If using, add the optional pinch of salt here.
• Whisk Eggs: In a separate small bowl, beat the 3 large eggs vigorously with a whisk until they are pale and noticeably increased in volume.
• Integrate Wet Ingredients: Pour the beaten eggs, melted butter (or coconut oil), peanut butter, and vanilla extract into the bowl containing the dry components.
• Mix Batter: Gently fold and mix the wet and dry ingredients using a spatula or the whisk just until a smooth batter forms. Be careful not to overmix.
• Portion and Top: Divide the batter evenly among the four prepared ramekins or mugs. Stud the top of each portion with the sugar-free chocolate chips.
• Bake: Place the ramekins/mugs in the preheated oven. Bake for approximately 17 to 21 minutes. The cakes should be set around the edges but can remain slightly soft in the very center if desired. Check with a toothpick near the center for desired doneness.
• Cool & Serve: Carefully remove the ramekins/mugs from the oven. Let them rest for 3-5 minutes to cool slightly and firm up before serving. Enjoy warm, optionally topped with low-carb ice cream, whipped cream, or an extra drizzle of peanut butter.

Notes

Yields: 4 individual mug cakes

Microwave Alternative:
For a quicker option, divide batter into 4 microwave-safe mugs. Microwave each mug individually on HIGH power for roughly 70-100 seconds, or until just cooked through but still moist. Cooking time may vary based on microwave wattage and desired texture.

Storage:
These mug cakes are best enjoyed fresh and warm.

Nutrition Information (Estimated Per Mug Cake):

Calories: ~386 kcal
Protein: ~12 g
Fat: ~36 g
Total Carbohydrates: ~29 g
Fiber: ~5 g
Sugar: ~2 g
Net Carbohydrates: ~6 g (Total Carbs minus Fiber minus Sugar Alcohols like Erythritol)
(Nutritional values are estimates based on standard ingredients and may vary based on specific brands used, particularly sweeteners and chocolate chips.)

Give It a Try!

Seriously, this recipe is such a lifesaver for quick cravings. It’s simple, satisfying, and feels incredibly indulgent. Go on, treat yourself! If you make it, I’d love to see – maybe tag me or drop a comment! Happy baking!