This 3 ingredient protein powder mug cake is a moist, fluffy, buttery chocolate cake that comes together in a matter of minutes. It contains no flour, no sugar, no gluten, and is low carb.
Add the butter to a large microwave-safe mug or small bowl. Heat in the microwave for approximately 45 seconds on 30% power to soften. Avoid melting completely as this will cook the egg.
Add the egg and whisk to combine the wet ingredients.
Add the protein powder and whisk until a smooth batter forms.
Microwave for 1 minute and 45 seconds (using a 900-watt microwave), then let it cool for a few minutes before serving. Top with a few chocolate chips, if desired.
NOTES
If your microwave has a different wattage, the actual cooking time will vary. Start with 1 minute, then add additional time as needed. Your mug cake will rise quite a bit and then deflate when fully cooked.
If your mug cake has a rubbery texture, it may have been overcooked. Try reducing the microwave time by 15 seconds.