Mix flour, sugar, baking powder, and salt in a large bowl.

In another bowl, beat the egg, then add milk, melted butter, and vanilla if using. Mix well.

Pour the wet mixture into the dry ingredients and stir until smooth.

Transfer batter into a greased microwave-safe container. Microwave on high for 1 minute 30 seconds to 2 minutes, until firm to the touch.

Let cool for a few minutes before serving. Enjoy plain or top with powdered sugar, fruit, whipped cream, or syrup.

Tips
Add lemon or orange zest for extra flavor.

Mix in chopped fruits like strawberries, apples, or bananas.

Divide into mugs for individual servings.

Decorate with whipped cream or fruit for special occasions.

Variations
Chocolate Cake: Add 2 tablespoons cocoa powder to dry ingredients.

Classic Vanilla: Use only vanilla or add ½ teaspoon almond extract.