Combine the Stonewall Kitchen Artichoke Spinach Dip Mix, cream cheese, and sour cream. Mix until uniform. Chill 20-30 minutes. Stuff each mushroom cap with mixture. Place on a greased baking sheet.
Make seasoned crumb topping by combining the breadcrumbs, melted butter, Parmesan cheese, and parsley. Toss until uniformly mixed. Top each mushroom cap with crumb topping. Bake for 15-30 minutes until filling has melted, the crumb topping is golden brown and the mushrooms are soft. If mushrooms are done before the crumbs are golden, place mushrooms under the broiler until crumbs brown. Serve immediately.