If the water is still draining slowly (not completely stopped), you may be able to dissolve the fat without taking the pipes apart.
: if the surface methods fail, you may need to manually clear the U-shaped pipe (P-trap) under the sink. Place a bucket underneath, unscrew the connectors, and clear out any solidified grease by hand. Prevention Tips To avoid future "fatbergs" in your plumbing, follow these NYC Environmental Protection guidelines: Scrape plates into the trash before washing to remove excess grease. Collect oil in a jar or container instead of pouring it down the drain. Flush regularly with a bit of hot water after cooking greasy meals to keep residue moving. Would you like a step-by-step guide on sink blocked with fat
If nothing works, the clog is likely located in the P-trap—the U-shaped pipe underneath your sink. This is the most common place for grease to settle and harden. If the water is still draining slowly (not