Add blueberries to a 13x9 inch baking dish. Set aside.
In a large bowl combine flour, walnuts, brown sugar, cinnamon, salt, and sugar. Slowly add melted butter. Use a fork and blend until small crumbs form. Sprinkle crumbs over the blueberries.
Bake at 375º Fahrenheit for 45 minutes until golden brown.
Notes
Serve with a scoop (or two) of vanilla ice cream. It's optional but highly recommended.