The central market is the best place in Torreón to eat cheaply and well. The food stalls inside serve gorditas filled with beans, chicharrón, or picadillo; enchiladas with red or green sauce; and aguas frescas in flavours that rotate with the season — jamaica, tamarindo, horchata. The market itself sells produce, dry goods, and household items, and has the organized bustle of a functioning neighbourhood institution rather than a tourist attraction.
Go for breakfast or lunch, when the stalls are busy and the food is freshest. Sit at the counter of whichever stall smells best and point at what the person next to you is eating — that is usually a reliable strategy. Prices are very low. The market is also worth browsing for dried chillies and spices if you are cooking elsewhere.