Add the mushrooms to a quarter sheet pan or a large mixing bowl. Add in the garlic, thyme sprigs, salt, freshly ground black pepper and olive oil. Toss to coat with the seasoning. Set aside.
1 large head maitake mushrooms, 2 cloves garlic, 6 - 8 sprigs fresh thyme, 2 - 3 tablespoons extra virgin olive oil, 1/4 teaspoon kosher salt, 1.4 teaspoon freshly ground black pepper