Quarter squid tubes lengthwise and score crosswise from one side. Later cut into 1 cm wide and 2 cm long strips. Boil water and blanch squid for about 1 minute together with 2 teaspoons of lemon juice.
Chop the garlic cloves, halve the onions and cut them into half rings. Mix the garlic cloves, chili paste, fish sauce, juice of one lemon and sugar to make a marinade. Mix the squid with the onions and the marinade. Bring the lettuce to the table on lettuce leaves and sprinkle with chopped peanuts.