Prep the Mushrooms:Clean the mushrooms by wiping them with a damp paper towel to remove any dirt or debris.Slice the mushrooms about 1/4-inch thick.
Sauté the Mushrooms:Heat the olive oil and butter in a large skillet over medium-high heat.Add the sliced mushrooms in an even layer and let them sit undisturbed for 2-3 minutes to allow them to brown on the first side.Stir the mushrooms and continue cooking, stirring occasionally, until they are golden brown and tender, about 6-8 minutes total.Add the minced garlic and thyme during the last 1-2 minutes of cooking, stirring constantly to prevent the garlic from burning.Season with salt and pepper.
Finish and Serve:Remove the sautéed mushrooms from the heat.Use the mushrooms immediately as a topping for your pizza, or allow to cool slightly before using.