Special equipment: a grill pan
Heat a large skillet over medium-high heat. Add the olive oil and 1 tablespoon of the butter and heat until nice and hot. Add the mushrooms and cook until they develop some good color and cook down quite a bit, 7 to 8 minutes. Add the minced garlic, season with salt and pepper and cook until the garlic becomes fragrant, about 1 minute.
Add the wine and cook until the wine reduces and there is no liquid visible in the pan, a few minutes. Add the parsley, the last bit of butter and a touch of lemon juice and cook the mixture long enough for the butter to melt.
Heat a grill pan over high heat. Grill the bread slices until they have visible grill marks, 1 to 2 minutes per side. Remove from the pan and rub on one side with the whole garlic clove.
Top each piece of the grilled bread with some of the mushroom mixture. Serve and enjoy!