In a skillet, cook bacon until crisp. Drain bacon and discard pan drippings. In the same skillet, cook onions in butter until tender. Cool. In a mixing bowl, combine sour cream, flour and salt; add eggs. Stir in the bacon and onions; set aside. Separate crescent roll dough into four rectangles. Pat dough into the bottom and 1" up sides of a greased 9" square baking pan, stretching as needed. Pinch edges together to seal. Pour onion mixture over dough. Bake at 375 degrees for 30 minutes or until the topping is set and crust is golden. Cool slightly before cutting into small squares. Serve warm.
