3 tbsp unsalted butter, DIVIDED
1 c coarsely chopped onions
1-1/4 lbs fresh white or crimini (brown) mushrooms, cleaned, trimmed and sliced
1 6-oz package herb-seasoned stuffing mix, about 4 c
1/2 c coarsely chopped walnuts
1/2 c finely chopped red bell pepper
In a large skillet, over medium heat, melt 1 tablespoon butter. Add onions; cook and stir until tender, about 5 minutes. Spoon into a large bowl.
Melt another tablespoon butter in the same skillet. Add half of the prepared mushrooms; cook and stir until golden, about 5 minutes. Remove to the bowl with the onions. Repeat with remaining butter and mushrooms.
Add 2 cups water to skillet; stir to loosen browned bits. Pour into mushroom mixture. Stir in stuffing mix, walnuts, pepper and salt to taste, blending well.
Spoon into a prepared shallow 2-to-3 quart casserole.
Bake in a preheated 350 degree F oven until hot and crisp on top, about 45 minutes.
Sprinkle with chopped parsley, if desired.