Start by cleaning the mushrooms thoroughly to remove any dirt.

In a large pot, add enough water to cover the mushrooms and bring it to a rolling boil. Once boiling, add the mushrooms and cook for about 10 minutes until tender. After cooking, drain the mushrooms and set aside.

In a smaller pot, combine the vinegar, water, sugar, salt, bay leaves, and fresh thyme. Bring this mixture to a boil to create the marinade.

Take a large jar and pack the cooked mushrooms into it. Add the garlic cloves, quartered onion, and extra thyme sprigs for added flavor!

Pour the hot marinade over the mushrooms, ensuring they are fully submerged.

Seal the jar and allow the mushrooms to marinate for about 3 days before tasting. Enjoy!