Pumpkin-Seed Sauce

I have been eating this version of pepián (also spelled pipián) ever since I can remember. My mother used to serve it with green beans, nopalitos (cactus paddles), or cooked veal tongue. It’s also good with Pollo Guisado, but in this case the chicken should be a little chunky, not finely shredded. We often serve it at Zar