Mix the 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 corn starch and 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 coconut shrimp.