Shake well and serve at once.
For Orange Milk Shake, substitute 1/4 tsp. orange extract for vanilla, or omit extract and add 2 tbsp. orange juice.
For Coffee Milk Shake, add 2 tbsp. strong coffee.
For Chocolate Milk Shake, add 2 tbsp. chocolate sirup to 3/4 cup.of milk and 2 tbsp. chopped ice.
Shake well and serve.