Preheat the oven to 350 degrees F. Lightly spray a standard 6-cavity doughnut pan with nonstick spray and set aside.
In a large bowl whisk together the flour, sugar, baking powder, and salt. In another bowl, whisk together the half and half, egg, butter and vanilla.
Add the liquids to the dry mixture and stir to combine until there are no longer any dry streaks of flour. Fold in the sprinkles until evenly distributed.
Using a piping bag (or spoon), fill the prepared doughnut pan about two-thirds full of batter. Bake for 18 to 20 minutes until toothpick inserted into the doughnuts comes out clean. Allow to cool in pan for 3 minutes before inverting the pan and unmolding the doughnuts.
MAKE THE GLAZE:
In a medium bowl, stir together the powdered sugar, half and half, and vanilla until smooth. Add a few drops of food coloring until desired color is achieved.
Dip the doughnuts into the glaze and immediately top with sprinkles. Doughnuts can be enjoyed immediately or once the glaze is set.