Blue Milk

Blue milk, was a blue-colored liquid produced by a female bantha’s mammary glands from the Star Wars world. It could be found on most planets across the galaxy. The milk was well known for being very rich and refreshing, its opaque coloring suggesting that it was also sweet. The milk was also used to make a variety of yogurt, ice cream, and cheese. Its ubiquity inspired the military phrase "blue milk run." Dex's Diner served blue milk.

Ingredients

 * 1 c. (8 oz.) vanilla soy milk, well-chilled
 * 1/2 tsp. unsweetened blue fruit punch mix
 * 1 tbsp. sugar, or to taste

Directions
Combine soy milk, fruit punch mix, and sugar in a jar or container with tight lid. Shake well, until the fruit punch mix has dissolved completely and the drink is frothy. Serve immediately.

Source
You can find more information about the recipe here.