These are so good, you may omit the butter but it is lovely to sop up the sauce with a bit of baguette. Use real bacon. I often use small Portabello mushrooms but either white, portabello or any mushroom typs large enough to hold the stuffing. Try using escargot bakers to hold the mushrooms this way you don't lose any of the sauce. Serve right in the escargot pan. If you don't have escargot pans just bake them on a tray or small oven proof dish -see picture. Make as many as you wish just allow 1 clove garlic for each mushroom. If serving as an appetizer/first course allow 5-6 mushrooms per person depending on the size of the mushrooms. If serving as a side dish to Brunch etc allow 2-3 per person.