Koreans have enjoyed the "hurts so good" school of cooking since at least the first half of the last millennium. Even then they were experimenting with a small arsenal of incredibly potent spices, including a popular strain of Chinese peppercorns known as tang chu, or the "suffering plant." The late 1500s brought Portuguese missionaries through Japan, loaded down with New World agricultural products. Their Godly message may have gotten lost in translation, but the spicy peppers they introduced certainly weren't. It was only a matter of time before chilies had migrated into what's now North and South Korea, where they've since become firmly rooted in Korea's culinary and cultural identity.
Go chu jang is to Korean cuisine what ketchup is to burgers and fries. It's a kind of fermented chile paste that's made from finely ground red chile powder, soy beans and brown rice syrup. This mixture is placed in a large, earthenware pot that sits outside on the family roof or patio, and is allowed to ferment for a few months to several years. The final result is a beautifully red gum with a smoky, penetrating heat, miso-like salty-ness and mellow, malted sweetness. The depth of flavor and color it lends to dishes is hard to beat, especially when swirled into soups or slathered onto steamed white rice, seafood or meat. Fortunately for those of us not skilled in fermentation, Korean red chile pastes are available in most Asian markets. I suggest that you avoid brands that use MSG, corn syrup and sugar, though. They're pale imitations of the real stuff.
The next thing I recommend you do is go out and buy yourself a brisket. A nice, economical "point cut," with some extra fat to keep your meat moist and flavorful (you can cut it off after it's done cooking, if you like). Put it in stockpot that's big enough to hold the whole thing and cover it completely with cold water. Throw a lid on the pot and bring it to a gentle boil (it should take about a half an hour) and keep it there for three and a half to four hours, adding more water if necessary.
While you're waiting on your meat, I should tell you that there's no system of precise measurements in traditional Korean cooking. Instead of relying on recipes, chefs are taught dishes through something called "fingertip taste." It's basically an intuitive way of cooking that's similar to the "pinch" and "dash" method that most home cooks use. I first learned how to make Korean-style barbecued brisket through fingertip taste.
When the meat is cooked all the way through and very tender, remove it from the water. In another pan, sauté several bulbs of crushed garlic (I use three whole ones) in sesame oil until it starts to soften a little. Add chile paste, sake and a few splashes of soy sauce. Barely simmer it until the garlic is tender and the sauce has been reduced to a thick, velvety, glaze. Make sure you've got enough to coat the brisket. Pull the pan off the heat and let it cool for a bit.
Poke holes in the brisket with a fork, then massage it liberally with your sauce. Tuck in pieces of garlic wherever possible. Let it sit for about 10 minutes. Fire up your grill (any kind works well. You can use a large stovetop pan or a broil it in your oven if none are available). Cook the brisket until both sides are crisp, which should be about 10 minutes. Transfer that beautiful spice baby to a platter and serve it on a table surrounded with family and friends.