Gaotang Laodoufu is a geographical indication certification trademark.

Gaotang old tofu is a specialty snack in Gaotang County, Liaocheng City, Shandong Province. Gaotang old tofu, also known as tofu brain, tastes smooth, tender and refreshing, with unique bean, seasoning and braised flavors. It is a famous Gaotang delicacy.

Gaotang Laodoufu is made from selected high-quality soybeans. Peel and crush the soybeans, then soak them in stored water that has been exposed to sunlight for a long time (purified Yellow River water is best). After the crushed soybeans have swelled enough, use a stone mill to grind them into a slurry. After foaming and bagging (filtering residue), put it into a pot and boil it into bean juice. After cooling down, put it into a bucket or cylinder, add gypsum, seal it, and it will be ready in 20 minutes. When eating, use a flat spoon to scoop it into a bowl and add ingredients such as marinade and oil.

The production of brine and oil is unique. Add water to the pot with high-quality soy sauce and refined salt for the brine, and add more than 10 kinds of seasonings such as star anise, pepper, fennel, cloves, cinnamon, and ginger to cook; use high-quality cottonseed oil to boil the oil over a slow fire, and remove oil foam and debris while boiling. . After a few hours, add onions, sweet sauce, pepper, fennel and other condiments. If you like spicy food, you can add fried red chilies.

Gaotang Old Tofu is famous both inside and outside the province. As early as the 1980s, it was featured on TV, newspapers and related publications, and was included in the "Gaotang County Chronicle" as a local famous food, making it famous both inside and outside the province. There is a saying that goes: if you go around a hundred meters to Gaotang, half a bowl of tofu will be delicious. It’s a pity that outsiders come to Gaotang and don’t drink Lao Doufu. It is a real pleasure for Gaotang people to sit in front of the stall and drink a bowl of old tofu after returning from an outing. Some leaders from inside and outside the province, business owners, new and old customers from surrounding areas, and friends from all walks of life came to Gaotang to drink Laodoufu. Many people in cities and towns often eat sesame seed cakes and old tofu for breakfast.