1¾ cups white wine vinegar, divided
1 cup water
4 garlic cloves, peeled and crushed
2 bay leaves
2 tsp. black peppercorns
1 lb. mixed mushrooms, such as king trumpet, oyster, button, and/or cremini
1/4 cup extra-virgin olive oil
Kosher salt
Combine 3/4 cup of the vinegar with the water, garlic, bay leaves, and peppercorns in a two-quart stainless steel saucepan and bring to a boil over high heat.
Add the mushrooms, return to a boil, and cook for two minutes. Remove the saucepan from the heat and let the mushrooms cool in the cooking liquid. When cool, strain and transfer to a bowl.
Combine the olive oil and remaining cup of vinegar, pour over the mushrooms, and set aside for 30 minutes. Season with salt to taste and serve.
Can be made three days ahead, covered, and refrigerated.
Serve at room temperature.