FOR THE NOPAL SALAD: Cut the cactus paddles into thin strips and place them in water with salt and a tomato peel (this helps remove the slime). Drain and transfer to a bowl. Wash the onion, Roma tomatoes, and cilantro; slice the onion and Roma tomatoes into half-moons and finely chop the cilantro. Add to the nopales with a little salt and mix well.

FOR THE SALSA: Wash the serrano peppers and tomatoes and cook them in water. Blend them well with a little salt and set aside.

Knead the masa harina with the baking powder. Take a portion of dough, make a well in the center, and add a little of the refried beans.

Shape into an oval and flatten.

Heat a griddle or skillet and brush both sides with oil.