How to make the Grimace Shake? Scoop out four scoops of vanilla ice cream into a blender. Add two scoops of frozen blueberries and two spoons of strawberry jam to the mix. Top it off with one cup of milk. Blend the mixture together until it forms a thick, purple milkshake. Pour into a glass of your choosing and feel free to top it off the whipped cream and sprinkles.