California Shrimp Curry on Avocado

12 ounces frozen shrimp
1 tablespoon butter
1 1/2 teaspoons curry powder
1/2 teaspoon salt or to taste
1 medium tomato, chopped
1 medium onion, chopped
2 tablespoons lime or lemon juice
1 cup sour cream
3 to 4 avocados, cut in half lengthwise and pit removed

Cook the shrimp. Melt the butter with curry powder and salt. Saute tomato and onion in the butter mixture. When soft, add lime or lemon juice, shrimp and sour cream. Remove from heat. Spoon into avocado halves and serve with rice and chutney.

Serves 6 to 8.