Rinse bell peppers, cut in half, remove seeds and ribs, quarter, place skin-side up on a baking sheet and roast in a preheated 220°C (approximately 425°F) oven until skin bubbles and blackens. Remove from the oven, cool, remove skin and cut bell peppers into strips.
Blanch tomatoes, peel, quarter, core and cut into cubes. Remove olive pits. Coarsely cut into bread cubes.
Mix oil in a bowl with vinegar and pressed garlic and season with salt and pepper. Mix bread in a large bowl with olive, capers, tomatoes, basil and bell peppers, drizzle with vinaigrette, mix and let rest for approximately 2 hours. Serve on plates.