Here’s How is a series where we share the best useful tips from our cooking adventures. We’ll answer questions before you have them and illuminate food mysteries with a blend of science and legend.

In this week’s Roast Beef with Horseradish Sour Cream & Heirloom Carrots, we bake up an eye-round beef roast and slice it thinly to serve with a salad, handsome heirloom carrots, and spicy horseradish cream. The flavorful slices will be tender, not because we cooked the meat forever (it’s only in the oven for 30 minutes) or because it’s a fatty cut (in fact, it’s pretty lean).

Nope, it’s because we slice against the grain.

Here’s how slicing against the grain works:

If you look closely at the meat when it comes out of the oven, you’ll see little lines running across it. In this case, they are perpendicular to the string tied around the beef. That’s the grain we’re talking about. Hold your knife crosswise to the grain and cut thin slices of meat

Here’s why¬†cutting across the grain makes meat tender, according to our chef Matthew Wadiak:

Meat is a muscle. For a tougher piece of meat especially, that muscle is long and stringy. You don’t want a long and stringy bite of meat. So when you cut against the grain of the muscle, you get hundreds of tiny fibers–instead of one long one. That makes the meat melt in your mouth.

Next time you cook a flank, hanger, or skirt steak, check out the grain in the meat before you sear it. The grain won’t always be as obvious as on our roast beef, but if you look carefully you’ll find it. And earn more tender meat in the process.

Check out a few more of our favorite steak recipes:

Got questions about any of the techniques in our recipes? Leave a comment or shoot us a tweet and we’ll answer your question in an upcoming post.