There was a department store in New England called Jordan Marsh. They had bakeries in several of their stores. This is where everyone bought their blueberry muffins. My mother has been making this recipe ever since I can remember and no one in my family ever uses any other recipe. My mother also mixes her blueberries with cranberries for a sweet/tart effect. She makes some with just cranberries but they are too tart for me.
Enjoy the recipe. I have for years.
Susan