2(8-ounce) cans crushed pineapple in its own juice, drained, juice reserved
Reserved pineapple juice
1/4cup vegetable shortening
Combine flour, baking powder and salt. Cut in shortening with a pastry blender or two knives. Stir in buttermilk until a shaggy dough forms. Refrigerate at least 15 minutes.
Turn dough out onto a floured surface. Roll to a thickness of a 1⁄8 inch. Cut in 4-inch circles. Stretch or pat as thin as possible. Spoon about 1 tablespoon pineapple onto half of each circle; spoon about 1⁄2 teaspoon butter on top of pineapple; sprinkle with 1⁄2 teaspoon sugar. Fold dough over to close and pinch seam.
Melt 2 tablespoons vegetable shortening in a large nonstick skillet. When hot, fry fritters, a few at a time, until golden brown and crispy, about 6 minutes per side. Transfer to a paper-towel lined baking sheet and keep warm in a 200F oven. Add more shortening to pan as needed and fry remaining fritters.
To prepare sauce, mix cornstarch and reserved pineapple juice in a small saucepan. When smooth, add butter and salt, and cook over medium heat until butter melts and sauce thickens slightly. Serve with fritters. Makes about 12 fritters.