Measure milk in a measuring cup.
Add vinegar and allow milk to sour like buttermilk for about 3-5 minutes.
Meanwhile, measure pancake mix, vanilla, egg, oil, powdered sugar, cream of tartar and sprinkles into a small mixing bowl.
Once milk has thickened pour into mixing bowl and whisk ingredients together.
Spoon pancake batter into buttered skillet or griddle.
Cook on one side until bubbles appear on surface and edges appear cooked.
This will take a few minutes.
Flip pancake and cook on remaining side until done another minute or so.
Place on serving plate and keep warm.
Makes about 8 six-inch pancakes.
Meanwhile, prepare frosting for pancakes.
To serve, place pancakes on a plate.
Drizzle generously with frosting.
Add more sprinkles, for garnish.