Step 1 Place the cactus in a saucepan and cover it with water. Add salt to taste. Boil 5 to 10 minutes.
Step 2 Remove the pan from the heat and cool the cactus completely. Drain the cactus and place it in a salad bowl. Add the tomatoes, onion, cilantro, oregano, lemon juice and salt to taste. Mix the salad until it's well combined.