Peanut Butter Mug Cake without Milk
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This Peanut Butter Mug Cake without Milk Recipe is rich, moist, and ready in minutes using simple pantry ingredients. It is made without milk and is a perfect option for when you’re craving peanut butter cake.
It is a quick single-serve dessert (or two can enjoy) that requires only a microwave and basic ingredients, with a texture that stays moist rather than dense or dry – if you do not overcook it in the microwave.
For a different flavour option, see my Chocolate and Vanilla mug cakes without milk.
Why this recipe works
This peanut butter mug cake is designed to stay soft and consistent without milk:
Warmed Peanut Butter
Gently warming the peanut butter makes it easier to mix through the batter, giving a smoother texture without clumps.
Balanced Moisture
A combination of butter, oil, and water keeps the cake moist without milk after cooking, rather than drying out in the microwave.
Lightened Crumb
Cornstarch helps keep the texture from becoming too dense, giving a softer, more cake-like finish.
Peanut butter mug cake video
Get Your PB Fix in Minutes.
A simple microwave mug cake that focuses on peanut butter as the main flavour. The goal is a soft, evenly cooked crumb with a rich, nutty finish in a single serving. Sam x
No milk used – still soft and balanced
Strong peanut butter flavour – smooth and rich
Microwave baked – ready in about a minute
Single-serve format – no waste or leftovers
Ingredients you’ll need
All-Purpose Flour
Provides structure while keeping the mug cake soft.
Cornstarch
Helps create a lighter, more tender crumb.
Granulated Sugar
Adds sweetness and balances the peanut butter.
Baking Powder
Gives the mug cake its rise.
Salt
Enhances flavour and balances sweetness.
Peanut Butter
The main flavour, adding richness and a soft texture.
Unsalted Butter
Adds richness and supports a tender crumb.
Water
Replaces milk while keeping the batter hydrated.
Olive Oil (or Neutral Oil)
Keeps the cake moist and soft after cooking.
Vanilla Extract
Rounds out the flavour.
Optional Toppings
Chocolate chips or extra peanut butter for serving.
How to make peanut butter mug cake without milk
Step 1: In a small mixing bowl, whisk together the flour, cornstarch, sugar, baking powder, and salt until evenly combined.
Step 2: Add the warmed peanut butter, melted butter, oil, water, and vanilla extract to the dry mixture. Whisk just until the batter is smooth and combined, avoiding overmixing, just until streaks of flour disappear, then stop.
Step 3: Pour the batter into the greased mug and gently smooth the top. Microwave on high for 60-70 seconds before checking. The top should appear set but slightly soft in the centre. If needed, continue microwaving in 10-15 second bursts until just cooked.
Step 4: Step 5: If using, add chocolate chips and drizzle over the extra warmed peanut butter. Enjoy warm straight from the mug, or carefully loosen the edges and lift out. Enjoy!
Tips for the best mug cake
- Warm the peanut butter – Helps it blend smoothly
- Don’t overmix – Keeps the texture soft
- Watch the microwave – Overcooking makes it firm and dry
- Let it rest – Helps the texture settle before eating
How to store
Cooked cake: If there’s any leftover, remove the mug cake from the mug and store it in an airtight container in the fridge for up to 2 days. Tip: If you prefer, you can leave it in the mug, covered loosely, but the bottom may be slightly more moist compared to storing in a container.
Reheating: Warm gently in the microwave for 10–15 seconds before enjoying.
More recipes without milk
Try these other cakes without milk including chocolate, date and apple!
Peanut Butter Mug Cake without Milk
Ingredients
Method
- Prepare the Mug: Lightly grease a microwave-safe mug (240–350 ml / 8–12 fl oz) with soft butter, coating the base and sides. Set aside.
- Mix Dry Ingredients: In a small mixing bowl, whisk together the flour, cornstarch, sugar, baking powder, and salt until evenly combined.
- Warm the Peanut Butter: Add the peanut butter to a small saucepan and warm over low heat for 30–60 seconds, stirring until it loosens into a smooth, pourable consistency. It should still be slightly thick but easy to mix into the batter. This can also be done in the microwave in short bursts.
- Add Wet Ingredients: Add the warmed peanut butter, melted butter, oil, water, and vanilla extract to the dry mixture. Whisk just until the batter is smooth and combined, avoiding overmixing, just until streaks of flour disappear, then stop.
- Transfer to Mug: Pour the batter into the greased mug and gently smooth the top.
- Microwave: Microwave on full power/high for 60-70 seconds before checking and until it has risen. The surface will look dry and set rather than glossy. You shouldn’t see any wet batter on top. The cake will pull away from the sides of the mug slightly, which is a good sign it’s cooked through. If needed, continue microwaving in 10-15 second bursts until just cooked. Let the mug cake rest for 1 minute in the microwave before removing. Microwave Wattage Note: This timing is based on my 900-watt microwave. If your microwave is more powerful, start checking earlier, around 50–60 seconds, to avoid overcooking.
- Prepare the Topping (optional): Warm the extra peanut butter (1 Tablespoon) in a small saucepan over low heat for 20–30 seconds until slightly runny and easy to drizzle.
- Serve: If using, add chocolate chips and drizzle over peanut butter. Enjoy warm straight from the mug, or carefully loosen the edges and lift out. Enjoy!