Make bulgur in bubbling salted water for 5-6 min. Put it on a colander and rinse.
Rinse and clean the vegetables. Cut peppers, celery and tomatoes into 1 cm cubes. Quarter the mushrooms, divide the broccoli into roses.
In a frying pan with olive oil, sauté shallot cubes and garlic, add mushrooms, peppers, celery and broccoli roses and sauté. Season with salt and pepper, lastly stir in the tomatoes.
Mix the vegetables with bulgur and arugula and form in a gratin dish. Sprinkle with Parmesan and gratinate briefly under the grill coil.