Heat a griddle or nonstick skillet over medium heat. Meanwhile, in a large bowl, combine the flour, cake mix, sugar, baking powder, soda and salt; set aside.
In a separate medium bowl, lightly beat the eggs with a whisk. Add the milk, butter and vanilla and whisk to combine. Pour the wet ingredients into the bowl with the dry ingredients and stir until fully mixed. Fold in the sprinkles.
Scoop portions of a scant 1/3 cup batter onto the griddle, leaving room for the batter to spread into larger rounds. When the pancakes begin to bubble, flip and cook for another 1-2 minutes. Transfer to a plate and cover with a kitchen towel to keep warm until serving. Serve with syrup or optional icing.
Mix together powdered sugar and whipping cream to reach desired consistency and taste. Pour over top individual stack of pancakes.
Allow the pancakes to cool completely, then transfer to a freezer bag. Store in the freezer for up to 2 months. Reheat in the microwave for about 30 seconds, or until hot.