Mix together pina colada mix, water, crushed pineapple, coconut, and powdered sugar in a sauce pan. Heat on medium-low temperature until sauce begins to simmer, stirring frequently.
Let mixture simmer slowly 10-12 minutes. Mix cornstarch and cold water together; add to sauce and blend well.
Let mixture simmer for 3-5 minutes longer while stirring during and after adding cornstarch. Remove from heat and bring to room temperature. Sauce is served at room temperature with Parrot Bay Rum Shrimp.
Makes: 4