Place the bacon in a skillet over medium heat and cook for 5 minutes, until slightly crisp. Set the bacon aside and drain half of the fat from the pan {chop when cool}. Saute sliced mushrooms, in the same skillet, stirring occasionally until mushrooms are slightly brown, about 4-5 minutes. Remove from heat. Place spinach in a bowl, and toss with bacon pieces, cooked mushrooms, and cherry tomatoes. Drizzle with vinaigrette {see recipe below}.