Step 1

Rinse and dry the mushrooms, or wipe the surface with a damp paper towel. Trim the stems and cut them into halves.

Step 2

Heat a large saute pan over medium-low heat. Add the olive oil. Once the oil is warm, add the onions. Saute until lightly brown and translucent, about 4 to 6 minutes. Add the minced garlic and thyme, saute for 30 seconds.

Step 3

Increase the heat to medium. Add the mushrooms, then sprinkle with salt and pepper. Saute until tender, occasionally stirring, about 4 to 5 minutes.

Step 4

Add the balsamic vinegar and soy sauce, stir and cook until most of the liquid evaporates, about 1 to 2 minutes.

Step 5

Add the butter and stir to coat the mushrooms, cook for 1 minute—season with salt and pepper to taste.

Step 6

Garnish mushrooms with chopped parsley.