Rasp the garlic with the microplane into a small bowl. Rasp the skin of the lemon into the same bowl and set aside.
Clean the mushroom with a damp paper towel or brush to get rid of any dirt. Cut the mushrooms into quarters if they are big and in half if they are small.
Get a big heavy bottomed pan hot. Add half the butter and wait until the butter gets foamy. You want the butter to be foamy and just about to turn brown. Add half of the mushrooms and move them around with the tongs until they are all laying flat.
Don't shake the pan at this stage too much and just let them brown and cook. Once they are brown, flip them to the brown the other cut side. Continue cooking until nicely browned on all side.
Once the mushrooms are nicely coloured remove from the pan and keep warm in another bowl. Continue cooking the other mushrooms with more butter just like before.
Once the mushrooms are nicely browned add the other cooked mushrooms and toss in the pan. Season the mushrooms heavily with salt. Add the parsley, lemon zest, garlic and a squeeze of lemon juice and turn off the heat.
Serve on a big plate to share.