There is a reason a braised short rib melts in your mouth while a quickly cooked one stays tough and chewy. Tougher, cheaper cuts of meat are loaded with collagen, the connective tissue that holds muscle together. Cook them fast and that collagen seizes up into something rubbery. Cook them low and slow in moisture, and that same collagen breaks down into gelatin, which bathes the meat in silky richness and makes it tender enough to pull apart with a fork.
The key is choosing the right cut for the method. Hard-working muscles like chuck, brisket, pork shoulder, and short rib have plenty of collagen and respond beautifully to braising and smoking. Lean, tender cuts like tenderloin have almost none, so slow cooking only dries them out. Match the cut to the technique and you set yourself up for success before the pot even hits the stove. The most flavorful results often come from the least expensive cuts.
Time and temperature do the rest. Collagen begins to break down in earnest around 160 degrees, but it needs hours at that range to fully transform, so resist the temptation to crank the heat to speed things along. A gentle, steady simmer in a covered pot, or a long stretch in a low oven, lets the meat relax and absorb flavor while it tenderizes. Give it the hours it needs, keep it moist, and a humble cut of beef becomes the most impressive dish on your table.
