For someone traveling from Mexico's fertile southern tier, arriving in the deserts of the north can be startling: A serene and empty landscape, save for the occasional pecan grove and stalwart cacti bearing prickly pears. The markets here are sparer, and at first blush the food seems more austere, too. You won't find as many moles as in the south, or three dozen varieties of chile. Beef and cabrito (kid goat), often wood-grilled, tend to have pride of place over pork. Corn tortillas, ubiquitous everywhere else, are rivaled here by ones made of wheat flour--a legacy of the Spanish, who planted wheat in irrigated fields along rivers. This is the spiritual home of the burrito, after all; here, it's a minimalist creation that bears little resemblance to the behemoths served in the States. And the quesadillas of the desert are incomparably delicious, thanks to the combination of that soft, rich flour tortilla and slices of smooth-melting, mildly tangy Chihuahua cheese, a legacy of Mennonite settlers, and the ideal complement to the nutty-tasting wrapper. Add to that any number of fillings, from strips of hot chiles to air-dried meat to nopales (cactus paddles), and you'll understand firsthand how satisfying and appealing the fundamental foods of the desert are.