Peperonata is a delicious summer side dish typical of Italian cuisine. It's made of peppers and onions stewed with tomato passata cooked with vinegar and sugar for the classic agrodolce flavour.
Slice the bell peppers, remove the seeds and white bits. Slice the onion.
Heat olive oil in a pan, when it’s hot add onion, sauté for 5-8 minutes then add the bell peppers. Cook for 10 minutes then add salt and pepper and the tomato passata and some of the water. Cover the pan with a lid and cook for 20/25 minutes, adding water if necessary.
At the end add the sugar and vinegar and mix to combine. Cook for a few more minutes and serve.