Put half a cup of millet in a pot with a cup of water, bring to a boil and let the millet swell.
In the meantime, scoop out the peppers, chop the leftovers. Dice the mozzarella, dice the celery, chop the spring onion and parsley.
Mix the bell pepper pieces, cheese, celery, onion and parsley with the cooked millet, season with salt and pepper and fill the mixture into the peppers. Put the tomatoes in a baking dish, season lightly with salt and pepper. Put the peppers inside and bake at 180°C for about 30 minutes.
This filling tastes really great, very fine and noble, I was quite surprised when I tasted it for the first time.