In early September Forbes turned to Seoul's coffee scene and singled out a blue three-story building in Mangwon-dong, Mapo-gu. The country now counts 95,337 coffee and beverage shops, roughly one for every 540 people. In a market where an americano starts at 1,500 won, this place asks 17,000 won for a bag of beans.
1.The address is 11 Poeun-ro 6-gil, Mapo-gu, a residential alley a few steps in from Mangwon Market. Deep Blue Lake takes the whole of a three-story building whose brick has been painted blue. Bar and roasting lab on the ground floor, seating on the second and third, though floor area and seat count have never been published. The sign reads coffee roasters, not cafe.
2.Coffee and beverage shops have doubled in seven years to 95,337, about one per 540 residents, on National Tax Service figures. The pace is said to have slowed after 2024. The floor price of an americano has come down to 1,500 won. Not competing at that floor is where this shop starts.
3.From the alley the first thing you see is the work counter behind the ground-floor window. Push the door and the coffee bar is on the left, the barista's station on the right, bags of beans lined along a stainless top. A handwritten slip stands between them, naming origin, farm and processing.
4.The upper floors are divided by color. The stair rail is blue and framed pictures lean against the landing. The second floor is pushed toward green with plants and mirrors, and the third puts blue cushions and a yellow dome lamp by the window. Painting the whole building blue is the cheapest advertising on this alley.
5.A Loring roaster sits at the back of the ground floor. It recirculates exhaust heat, which the maker says cuts fuel by around 60 percent. Lee Chul-won picks stones and debris out of the green coffee before roasting and adjusts the roast to moisture content. Afterward he measures bean color against his target.
6.Because the roast is light, what rises from the cup first is fruit rather than char. The Ethiopia Guji Laro Boda washed leans citrus and floral, the Colombia El Placer Geisha honey carries a long sweetness. Lee tastes his brew again at 10, 20 and 40 minutes. That window separates coffee that collapses as it cools from coffee that holds.
7.One line sits apart on the menu board at the register. Order an americano and you may choose between two coffees. At that moment the customer stops drinking and starts choosing. Deep Blending mixes India, Guatemala and Ethiopia while Blue Blending pushes Ethiopia to 60 percent, and whoever remembers which one they picked is the one who leaves with a bag next time.
8.Forbes wrote in early September that in a market where anyone can sell a cheap iced americano, making unusual coffee has become a survival strategy. The roastery named in that piece, as carried by Seoul Economic Daily, is this one. Foreign visitors do not change trains for Mangwon-dong because of the room or a famous dessert. They come for a cup they can drink nowhere else.
9.On a recent sourcing round Lee tasted 23 samples and bought four. Rare microlots at auction can pass 1.5 million won per kilogram, the English edition of Seoul Economic Daily reports. Roasting only after an order comes in is the house rule.
10.Drinks run 5,000 won for espresso, 5,500 for an americano and up to 7,000 for brewed coffee. Three or four times a budget chain americano. Swapping dairy for oat milk costs nothing extra, and this is widely credited as the first shop in the country to bring in Oatly.
11.A 220g bag of beans starts at 17,000 won and climbs to 30,000. The menu board says a bag of beans comes with a free americano. A 5,500 won cup handed over in exchange for a 17,000 won bag.
12.In pure revenue the cups come to nearly four times as much. Those twelve cups drag seats, time, milk and washing up along with them. A bag costs paper and a label, and that customer never takes a seat. Which is why the free cup for a bean buyer is arithmetic rather than generosity.
13.Occupancy costs more when you take a whole building. A ground-floor retail unit of 49.5 square meters in Mangwon-dong is listed at around 30 million won deposit and 2.5 million won a month. Going up to the third floor raises rent by that much and adds someone to carry and clear cups on every floor. Putting the roasting lab on the ground floor is not free either. It costs selling area and buys the sight of roasting from the street.
14.The root of this approach is Nordic. The light, acidity-forward roasting style reached Korea in the mid-2010s, and this shop has long been counted among its leading names. On equipment alone it is an American roaster and a Dutch espresso machine. A small roastery on a Seoul residential street standing in the same line as a European workshop.
15.Is a flood of tourists always good for a micro-roastery? More guests who sit long and leave with a photograph means more washing up and fewer bags out the door. Letting customers choose the coffee, writing the name on the glass, adding a cup for the bean buyer, all of it points the same way. Toward standing the customer in front of the bags rather than the register.
16.The blue three-story building Forbes singled out sells an americano at 5,500 won, sends out bean bags at 17,000, and throws in that cup for whoever buys a bag. Anyone building the same structure in Korea splits at business registration. Roasting on site and selling bags to customers there runs under an on-site manufacturing and sales filing, but the moment it turns into wholesale to other cafes it needs a separate food manufacturing and processing registration. Plan a roastery on a simple beverage-service filing alone and the bag revenue never reaches the books.