Salt
1 pound (455 g) cactus paddles, cleaned (see this page) and cut into 1/2-inch (12-mm)
cubes
2 large Roma tomatoes, cubed
¼ cup (30 g) diced red onion
1/2 cup (20 g) chopped fresh cilantro leaves
½ teaspoon freshly ground black pepper
1 pound (455 g) queso fresco, cubed

Bring a large saucepan of water to boil and season it well with salt. Add the cactus, return it to a boil, then reduce the heat and simmer for 3 to 4 minutes, until the pieces darken to a slightly muted green and are cooked through. Drain and let them cool. In a large bowl, combine the cactus, tomatoes, onion, cilantro, 1 1/2 teaspoons salt, and the pepper. Gently fold in the queso fresco. Cover the bowl with plastic wrap and refrigerate for 1 hour before serving.