Preheat the oven to 180 degrees.
Wash and clean the aubergine, cut it into cubes and place them in a bowl full of water with salt and a tablespoon of vinegar or juice of one lemom.
Wash and clean the red and yellow pepper and cut them into small pieces (strips or squares).
Cut the onion into petals and slice the cloves of garlic.
Drain the cubes of aubergine and spread them around a big pan.
Then add the red and yallow pepper, the petals of onion, the slices of garlic, raisins, sugar, salt and pepper.
Sprinkle with the apple cider vinegar, olive oil ... and stir.
Put the mixture into the oven and roast it untill the aubergine cubes are tender and lightly browned.
Then remove the mixture from the oven and sprinkle with chopped walnuts, oregano and a little bit more olive oil.
Let the mixture cool to room temperature before serving.