In your microwave-safe mug, add the 2 tablespoons of Nutella and the large egg. Use a fork or whisk to mix these two ingredients until they are well combined and smooth.
Add the 1.5 teaspoons of sugar (or your sweetener of choice) to the mug. Stir it in well until fully incorporated.
Next, sprinkle in the 1 tablespoon of unsweetened cocoa powder and the 1/4 teaspoon of vanilla extract. Mix until everything is smooth and no lumps remain.
Add a dash of sea salt to the mixture. This small addition will enhance the sweetness and chocolate flavor.
Place your mug in the microwave and cook on high for about 1 minute. Keep an eye on it as microwaves can vary; if it needs more time, check in 10-second intervals.
Once your cake is done, carefully remove it from the microwave (it will be hot!). Let it cool for a moment before digging in. Enjoy it straight from the mug or transfer it to a plate.
