Thaw shrimp. In a large saucepan, bring 3 cups of water, cream, butter and salt to a boil.
Reduce heat to medium and whisk in grits. Cook 7-8 minutes, whisking constantly, till mixture is smooth.
Stir in the shrimp, cheese, and garlic. Cook 1-2 minutes.
I got this recipe from a friend who served it at her daughter's wedding supper.