Add the wet ingredients and whisk with a fork until there are no more lumps.
Spray a microwave-safe cereal bowl with non-stick baking spray. Pour the batter into the bowl.
Microwave on high until the center is set, about 2 1/2 minutes. (For reference, I use a 1200 watt microwave. Adjust your cooking time according to the wattage of your microwave.)
Turn the bowl out onto a plate to release the cake and let cool for 5 minutes.
Make the glaze
In a small bowl, whisk together the glaze ingredients.
Pour the glaze over the cake, top with sprinkles, and serve!