Directions

1. In a large bowl, combine masa harina, salt, and water, kneading with your hands until a smooth ball forms. Masa should be moist but not sticky. Cover with plastic wrap and let rest about 30 minutes for the moisture to even out.
2. While dough rests, prepare filling: Set a large frying pan over medium-high heat. Squeeze chorizo from casings into pan, discard casings, and cook chorizo, breaking up pieces, until it starts to get crisp, 3-4 minutes. Transfer chorizo to a plate and discard fat from pan.
3. Reduce heat under frying pan to medium and add 1/2 Tbsp. vegetable oil. Add onion and cook, stirring frequently, until onion is tender, about 3 minutes. Add mushrooms and continue cooking, stirring often, until tender, about 10 minutes. Fold in cooked chorizo, then set mixture aside until cool enough to handle, about 10 minutes.