Score the tomatoes along the stem. Blanch in boiling salted water until the skin begins to burst. Run under cold water, then peel the tomatoes. Cut into quarters, remove the seeds, and finely dice.
Rinse and trim the peppers. Cut in half, remove the seeds, and finely dice.
Peel and finely chop the onion.
Peel and finely chop the garlic.
Place all the prepared ingredients in a bowl. Mix in the olive oil and lemon juice, then season to taste with salt, pepper, and sugar. Serve with toasted white bread or grilled meat.