Sweet and Sour Shrimp

2 lbs. cooked shrimp
2 cups pineapple chunks
2 Tbsp. grated green or crystallized ginger root
1 green pepper, cut into long slivers
1/2 cup butter or cooking oil
1 cup pineapple juice
1/4 cup sugar
1/2 cup vinegar
1 Tbsp. soy sauce
2 1/2 Tbsp. corn starch
1/2 cup water

Combine shrimps, pineapple chunks, ginger root, and green pepper. Heat butter and cook mixture in it for 2 minutes. Add pineapple juice, sugar, vinegar, and soy sauce. Mix corn starch with water to make a paste. Stir into shrimp mixture and cook over medium heat, stirring constantly, until thick and clear. Serve with rice.