2 tbsp olive oil
1 onion, chopped
2 garlic cloves, chopped
2 courgettes (zucchini), sliced
4 tomatoes, skinned
400 g (14 oz) can flageolet (small navy) beans, drained and rinsed
10 black olives, halved and pitted
1 tbsp capers
1 tsp caster (superfine) sugar
1 tbsp wholegrain mustard
1 tbsp white wine vinegar
200 g (7 oz) can tuna fish, drained
2 tbsp chopped fresh parsley chopped
fresh parsley, to garnish
crusty bread, to serve