Beijing Roast Duck: It's the most famous, but it's not easy to keep its original flavor after taking it back. You can also buy some for your relatives to taste. Be sure to buy Quanjude. There are too many fakes in the market. Go to his restaurant (Heping Store, Qianmen Store and Wangfujing Store) to buy vacuum-packed lotus leaf cakes and his special roast duck sauce. Roast duck in the microwave at home. Steam the lotus leaf cake in a pan, cut some onions, dip it in roast duck sauce and roll it up.
Chestnut in Liangxiang: Yes, there are bags and gift boxes in the supermarket, which are convenient to carry and keep.
Pickles in Beijing: There are many kinds of pickles in bags and bottles in supermarkets. Liubiju and Tianyuan Sauce Garden are the most famous, and I think Tianyuan's is better. Tianyuan's hemp silk is great, and the honey in sweet sauce is also good.
Zhajiang Noodles: Do you know how to fry sauce? If yes, buy several generations of dried yellow sauce and give it to your family to taste Beijing Zhajiang noodles. It is also the most famous sauce garden in Liubiju and Tianyuan, and the best food is Guixinzhai in Beijing. Now it has been swallowed by Liubiju, but it also makes its own dried yellow sauce, with the trademark Liubiju and the name Guixinzhai, which is different from Liubiju's sauce. The real old Beijing loves his sauce, which is not easy to see in the supermarket.
Sugar-coated haws: There are small bags in the supermarket.
All the above things can be bought in big supermarkets except roast duck, and the price is cheap. Go and look around.