Preheat oven to 350°F and grease a mini donut pan** with nonstick cooking spray; set aside.
In a medium mixing bowl, whisk together flour, sugar, baking powder, baking soda, salt, and cinnamon. In a small mixing bowl, whisk together yogurt, egg, milk, oil, and vanilla extract. Add wet ingredients to dry ingredients and stir together until just combined. Do not overmix. Fold in the sprinkles.
Transfer batter to a large ziploc bag. Cut the tip of the corner off, creating a pastry bag. Fill each well in the donut pan about 3/4 full.
Place in the oven and bake for 7-8 minutes, or until donut springs back when gently pressed. Remove from the oven and allow to cool in the pan for 5 minutes before transferring to a wire rack to cool completely.
To make the glaze, whisk together the powdered sugar, vanilla and milk, starting with 2 Tablespoons. Add more milk, if needed. Pour about a third of the glaze into a small bowl. Add a drop each of pink and blue food coloring, swirl with a toothpick, then drizzle in more white glaze if colors are too dark. Dip donut halfway into the glaze, twist, then lift and shake off excess glaze. Place onto a wire rack. Repeat with the remaining donuts. Decorate with gold dust. Allow glaze to set/dry before covering or storing in an airtight container for up to 5 days.