Open the crab meat. go through it to check for shells if you bought pre picked lump crab. if you are using fresh steamed crab pick through. put crab meat into a bowl and set aside in the fridge covered

Dice onion, garlic if using fresh and celery if your using these.

Rinse or just clean the mushrooms. some people like to wipe them but I rinse clean

Heat a frying pan with butter pepper old bay and garlic. eyeball it. don't add to much spice unless you want these spicy as you will be adding additional spice later

Put the mushroom caps in the frying pan. saute them for about 10 to 20 minutes. turning them over a few times. you want some of the flavors to get into the mushrooms. you can cook longer or shorter if you like

Pull out crab meat and anything else you are adding into the mix.

Add mayonnaise mustard and spices into the crab meat. mix well. don't make it to runny. you want this thick

Scoop crab mix into each mushroom cap. I usually add in the left over butter and garlic from the frying pan, but I didn't have much left so I added butter. You can use something else instead of butter.

Add the reserved liquid to the bottom of the pan. place mushrooms on top of liquid.

Pull out the caps and remove foil. bake for additional time depending on your taste. I like mine to be a bit brown on top. I just watch them constantly to keep them from burning