Step 2 · Apply Boiling Water
Boil a full kettle or a large pot of water. Once boiling, very carefully and slowly pour the entire amount of water directly into the clogged drain. Pouring slowly gives the hot water time to work on melting the solidified grease. Wait about 10-15 minutes, then test the drain with hot tap water. If the water starts to drain, even slowly, repeat the process with another pot of boiling water to flush more of the grease away.