Preheat oven to 180 degrees Celsius.
Combine the oil with the balsamic vinegar, garlic, herbs and seasoning in a small jar. Chop the mushrooms into chunks and halve the tomatoes. Pour over the dressing and leave to marinate for 30 minutes.
Fill the capsicum halves with the mushroom mixture. Lay them onto a baking tray. Cover with foil and bake for 30 - 40 minutes until the capsicum is tender.
Serves 4 as an accompaniment to protein or as a light lunch.