Heat avocado oil in a large skillet with minced garlic. Add shiitake mushrooms (some chopped, some whole) and cook for about 15 minutes on a low medium heat.
To the skillet add the balsamic vinegar, peas, and green beans. Continue cooking allowing the mixture to thicken. Once almost all the liquid is dissolved, add in the thyme, chopped chives, and parsley. Cook for a minute or two longer then turn off the heat.
Polenta
Add salted water to a saucepan and bring to a boil. Whisk the water while pouring in the polenta. Make sure you pour in a slow, steady stream. Stir continuously until the mixture starts to thicken. Add in the plant based milk and stir. Keep covered and stir every five minutes until it's no longer gritty, about 30 minutes.
When it's done cooking, mix in the vegan butter and sea salt
Plate the polenta and top with the mushroom mixture. Top with additional fresh parsley, thyme, sea salt, and pepper.