2. Wash the potatoes, put them in the pot, add a lot of cold water, boil the water until it boils, and continue to cook on medium heat for about 30 minutes. You can easily insert them with bamboo sticks. (potatoes must be boiled with skin to keep the skin from getting wet; Boil potatoes in cold water, let the temperature slowly enter the inside, to avoid excessive difference in cooking degree between inside and outside)
3. Peel the potatoes, put them in the finest grinding net, and press out the delicate mashed potatoes. Don't use a blender, the mashed potatoes will be burnt and taste bad. )
4. Put the pressed mashed potatoes into a non-stick pan and stir with slow fire for 5 minutes. (evaporate some water to make the taste more rich and mellow)
5. Cook whole milk with slow fire when heating mashed potatoes.
6. Add butter cubes that are cold enough (keep the nail size for later use). Butter cold enough will slow down the melting time, make the butter mix more evenly and make the mashed potatoes more sticky.
7. Stir until the butter is completely absorbed by the mashed potatoes.
8. Add the milk with extremely high temperature and stir constantly to make the milk completely absorbed by mashed potatoes. Season with salt and white pepper. Don't use black pepper, it will look like impurities.
9. Put the mashed potatoes into a bowl or squeeze them into a certain shape. After melting a small piece of butter, brush it on the surface of the mashed potatoes, which will form a thin layer isolated from the air to prevent the mashed potatoes from drying out and make the surface fragrant.