I've eaten lunch here several times since its opening in Jan 2012. Pretty easy because I live 3 blocks away. I like the food very much. It is always kept very clean. There are usually many customers when I go but it's never real crowded, not because it's unpopular but I think rather because I just happened to be there at non-peak hours. Service is good, fast, and helpful. I don't speak any Korean, although my wife is Korean so she helps with communication, but the staff knows enough English so that non-Koreans can survive just fine. The cost is about normal for a large buffet.
When you sit down at your table, one of the staff starts up your gas grill in the center of the table. You go to the buffet food section and select your food to be barbecued. They have the Korean marinated beef short ribs, kalbi, as well as bulgogi, made with a different marinade. They also have spicy pork, sausage (sweet Italian type, I believe), and some other treats like intestines (not sure if they were beef or pig). You bring your plate back to your table. The staff will come over and cut up the meat into smaller pieces if necessary and then place them on the grill. Or you can do it yourself and do the rest of the cooking. The staff will come over quite frequently to check on you and the food on the grill. They also will change the grill plate as needed when it gets very brown and grimy. The new plate upon heating gives off the smell of a something having been freshly scrubbed with a Brillo pad, a metallic soapy odor that I always notice immediately and bothers me a little bit but it disappears quickly.
They have an adequate selection of other buffet foods, either cold or already cooked. Not an enormous variety but quite sufficient. There are the usual banchan selections, various kimchi types, Korean pancakes, and mandoo, those great huge Korean dumplings, either fried or steamed. They have various salads, rice, soups, cooked chicken wings. They only have a few fresh fruit choices. And usually only one or two Korean desserts, as typical for their restaurants..
Although there is a fume hood directly above the grill at each table, it's fairly high up and not super-strong, and one big problem you'll encounter is that your clothes will pick up the food smell. However this problem is going to be pretty common for all Korean barbecues.
There are other Korean barbecue restaurants in the area that have charcoal grills instead of gas. Some prefer highly the charcoal grill, but I think the gas grill works just as well. There's another place nearby where I prefer their marinated beef, just a bit more tasty to me, but Picnic Garden is still very good.
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