Preheat oven to 350 deg F. Saut? onion and mushroom stems in bacon fat until tender. Drain off excess fat. Mix crumbled bacon, onion, and stems w/ softened cream cheese until the mixture is workable. Doctor it up with cavender's greek seasoning, lemon pepper, and garlic salt to taste. Stuff each mushroom and place in 9 x 13 pyrex. Pour melted butter between each mushroom before baking. Bake for 10-20 minutes. Finish under the broiler (low) for about 2 minutes, just until the tops are golden.