What is the use of expired coffee powder?

Although expired coffee powder can no longer be drunk, coffee has the effect of absorbing peculiar smell and can turn waste into treasure. The cooking pot at home has been used for a long time, inside and outside is full of greasy, but also has a peculiar smell. Put the expired coffee powder or boiled coffee grounds in the pot and roast it over the fire, and the greasy and smell in the pot will gradually disappear. An oven in which delicious food is often baked at home.