Prep the swiss chard by washing well. Cut off the bottom 1/3 of the stem then slice remaining stems & leaves into 1″ wide ribbons. Add the olive oil to a pot, heat over medium heat. Add the garlic and sauté for 1 minute. Then add the swizz chard, mix it to coat in the oil, turn the heat to medium-low and cover with a lid. Let cook for about 5-10 minutes, stirring occasionally. When greens are wilted add the butter and mushrooms. Season with onion powder, red pepper flakes, salt & pepper, cover with lid and let cook another 5 minutes. Remove the lid and let cook for another 5 minutes or so until the mushrooms and greens are tender. Adjust seasoning as needed.