2 tablespoons (28 g) unsalted butter, softened or melted and cooled
3 tablespoons (45 g) smooth applesauce
1/2 teaspoon pure vanilla extract
2 tablespoons (25 g) granulated sugar
1/8 teaspoon kosher salt
1/2 teaspoon baking powder
1 teaspoon edible gluten free confetti, nonpareils, or sprinkles (optional)
Grease microwave-safe mug or mason jar with at least an 8-ounce capacity and set it aside. In a mixing bowl or measuring cup, place the butter and applesauce and whisk vigorously to combine very well. Add the sugar and salt, and whisk again to combine. Add the flour blend and baking powder, and whisk until smooth. Add the optional edible decoration, and mix until evenly distributed throughout the batter. Pour the batter into the greased mug, and smooth the top.
Place the mug in your microwave oven and cook at about 1000 watts for 1 minute 45 seconds. Test with a toothpick to see if it comes out clean. If not, cook for up to another 20 seconds at about 1000 watts. Allow to cool briefly before serving.