Dice the chicken and marinate for 10 minutes. Remove the seeds from the tomatoes and dice.
Heat the oil pan, stir-fry the spinach and add the garlic to taste.
Preheat the oven to 200 degrees.
Apply a little olive oil and tomato sauce to the mushroom; put the tomato, spinach and chicken onto the mushroom cap. Sprinkle with dried herbs. Bake in the oven for 15 minutes.