Cut squid tentacles and bodies crosswise into ½ inch rings. Be careful to remove the ink sac without breaking it. It will give a dark color to the ceviche.
Place the squid pieces in a strainer or colander and pour boiling water over them. Squid pieces can also be cooked in boiling water for 1 minute. Drain and place squid in a serving dish.
Blend garlic cloves with fresh yellow aji and lime juice until creamy and pour over squid. Season with salt and white pepper. Cover with chopped onion and marinate for 30 minutes.
Garnish with rocoto (hot red aji) slices and chopped parsley.
Squeeze more lime juice if necessary.
Serve with peeled tomato wedges around the squid ceviche.