Prepare the Mug Cake

1. Mix the Dry Ingredients: In a microwave-safe mug, whisk together the flour, sugar, baking powder, cinnamon, and salt until well combined.
2. Add the Wet Ingredients: Add the milk, melted butter, and vanilla extract to the dry ingredients. Stir until smooth, ensuring there are no lumps.
3. Microwave the Cake: Microwave the mug on high for 1 minute. Check the cake, and if it’s still a bit gooey in the center, microwave for an additional 15-30 seconds. Every microwave is different, so keep an eye on it! The cake should rise slightly and look set on top.
4. Prepare the Topping: While the cake is cooling slightly, mix together the sugar and cinnamon in a small bowl. Sprinkle it evenly over the top of the warm mug cake for that classic snickerdoodle flavor.

Serve and Enjoy

1. Enjoy Warm: Allow the mug cake to cool slightly (but not too long!) before enjoying it. The cake is best when it’s still warm and soft, right out of the microwave.
2. Add Extra Toppings (Optional): If you’re feeling indulgent, top it with a scoop of ice cream, a drizzle of caramel sauce, or even a dollop of whipped cream.