If you’re craving a rich, gooey dessert but don’t want to wait, this Molten Peanut Butter Lava Mug Cake is the answer! Ready in just 5 minutes, this easy microwave mug cake combines the irresistible flavors of chocolate and peanut butter with a molten lava center.
It’s the perfect single-serve dessert when you need a quick chocolate fix, with a light, fudgy texture thanks to whipped cream folded right into the batter. Move over chocolate lava cake—this decadent peanut butter mug cake will be your new favorite treat!
Mug cakes have long been a favorite on our site and this simple throw together molten peanut butter mug cake is so quick and easy, you’ll add it to your list of favorites too!
For this recipe we use homemade whipped cream, it’s actually very easy to make your own with this wonderful whipped cream dispenser to ensure you’re using real cream rather than an oil-based dairy substitute.
To use the homemade whipped cream maker, all you need to do is pour in fresh whipping cream, add 1 or 2 drops of vanilla extract, screw on the top, apply the N20 gas cartridge, give it a good shake until the can feels nice and cold in your hand, and invert and squeeze trigger.
Having said that, any store-bought (real dairy) whipped cream in a can would likely work just fine.
Molten Peanut Butter Lava Fudge Mug Cake Video
How to Make Peanut Butter Lava Fudge Cake
You’ll Need:
non-stick cooking spray
1 heaping spoonful of Peanut Butter
Whipped Cream (already whipped, not liquid)
1 Large Egg
1/2 cup Chocolate Fudge Brownie Mix, (Dry)
- Spray the inside of a microwave-safe mug with non-stick cooking spray (be liberal about it!).
- Crack an egg into the mug, add the brownie mix, fill the remaining space in the mug with whipped cream- about 1/2-2/3 of a cup.
- Mix with a fork until completely blended.
- Add a generous dollop of peanut butter to the batter, about a rounded tablespoon.
- Microwave on high for 1 minute, and 10 seconds, exactly.
- Remove the cake from the microwave and immediately invert the cake onto a serving dish.
- Garnish with a touch of Whipped Cream & serve immediately.
Single Serve Molten Lava cake dessert in less than 4 minutes flat!
Who knew dessert could be so easy?!
💸 Budget101® Price Breakdown: Molten Peanut Butter Lava Fudge Mug Cake
Ingredient |
Amount Used |
Package Size |
Full Package Cost |
Used Cost |
Dry Brownie Mix |
½ cup (60g) |
18.3 oz box (519g) |
$1.24 |
$0.29 |
Large Egg |
1 egg |
12-count carton |
$1.98 |
$0.17 |
Whipped Cream (already whipped, from dispenser) |
½ cup |
1 pint heavy cream (yields ~4 cups whipped) |
$3.68 |
$0.46 |
Peanut Butter |
1 tbsp |
16 oz jar |
$2.12 |
$0.10 |
Non-Stick Cooking Spray |
Light coating |
6 oz can |
$2.48 |
$0.03 |
💸 Budget101® Price Breakdown for the Molten Peanut Butter Lava Fudge Mug Cake based on average Walmart prices (as of May 2025)
🧾 Total Used Cost: $1.05 per mug cake
✨ Optional toppings (extra):
- Additional whipped cream garnish → +$0.10
- Chocolate drizzle or sprinkles → +$0.05
✅ This makes it an affordable single-serve dessert for just about $1—perfect for Budget101’s frugal kitchen hacks!
Tried this recipe? Mention @Budget101com or tag #Budget101
📌 Love this Easy Molten Peanut Butter Lava Fudge Mug Cake Recipe? Pin it!
🖨️ Print-Friendly Peanut Butter Lava Fudge Mug Cake Recipe


Molten Peanut Butter Lava Fudge Mug Cake
Equipment
- 10oz mini trifle bowl (as shown in video) or Lg Coffee Mug (12oz)
- Fork
- whipped cream dispenser (or canned whipped cream)
- Microwave
- Small serving plate (optional for inverting)
Ingredients
- non-stick cooking spray
- 1 Tablespoon Peanut Butter (well rounded)
- ½ cup Whipped Cream
- 1 large Egg
- ½ cup Chocolate Fudge Brownie Mix, dry
Instructions
- Spray the inside of a microwave-safe mug with non-stick cooking spray (be liberal about it!).non-stick cooking spray
- Crack an egg into the mug, add the brownie mix, fill the remaining space in the mug with whipped cream- about 1/2-2/3 of a cup.1 large Egg½ cup Chocolate Fudge Brownie Mix, dry½ cup Whipped Cream
- Mix with a fork until completely blended. Add a generous dollop of peanut butter to the batter, about a rounded tablespoon.1 Tablespoon Peanut Butter
- Microwave on high for 1 minute, 10 seconds.
- Remove from microwave and immediately invert the cake onto a serving dish.
Equipment
If you altered the ingedients above by doubling or tripling the recipe, you may also need to change the pan/dish size and adjust the cooking/baking time.
Nutrition
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