1. Take mushrooms and slice off the woody ends and mushrooms caps. Slice the stems into 1 inch long pieces.
2. In a large mixing bowl, whisk together hot vegetable broth, white miso, soy sauce, and olive oil. Whisk until the miso has dissolved in the hot broth.
3. Add the mushrooms and marinate for 15 mins to 2 hrs. Overnight is preferred.
4. After your mushrooms have marinated, melt 1 tbsp butter in a large skillet over medium-high heat.
5. Working in batches, place marinated mushrooms, flat side down, and brown for 6-8 mins on each side. Set aside and keep warm.