Wash the mushrooms under running water, cut off the tips of the legs. If you have large mushrooms, cut them in half. Heat the pan and add the olive oil. Transfer the mushrooms to the pan, season with salt and fry until tender.
Wash the cherry tomatoes and cut them into 4-6 pieces. Cut the mozzarella balls in half. Wash and dry the arugula.
Place the tomatoes, mozzarella, and arugula on a plate and season with salt and pepper to taste.
Top with warm mushrooms, drizzle with olive oil and balsamic vinegar. Stir.