Such a classic, authentic recipe.
Adapted from smitten kitchen
To marinate overnight:
6 bell peppers (if you can get a mix of colors, go for it)
splash of red wine vinegar
Salt, to taste
1 clove of garlic, minced
Roast at 200 deg C for 1 hour, rotating every 15 minutes. Let cool. Remove skins. Slice into strips. Toss with the vinegar, garlic, and salt. Refrigerate overnight.
Freshly ground black pepper, to taste
2 glugs of extra-virgin olive oil
2 spoonfuls of capers, drained
some flat-leaf parsley, chopped (optional)
1/2 pound ball of mozzarella, sliced (use the really fresh stuff, if you can get it =)
Eat with crusty bread and a glass of red wine.