In a bowl, mix the chicken cubes with 2 tablespoons of olive oil, garlic, oregano, salt and black pepper. Marinate for 30 minutes.
Cut the pepper, onion and tomato into squares.
Remove the meat from the marinade and string it on wooden skewers alternately with vegetables (pre-soak the skewers for 20 minutes in water so that they do not burn). Salt and pepper to taste.
Cook on the grill until tender, turning from time to time and pouring a mixture of olive oil and lemon.
