If your kitchen sink is clogged with grease, the best thing I've ever found is Dawn Dishwashing Liquid. I plug the drain and put a huge squirt, maybe 1/2 cup, in the sink. Then I fill the sink with boiling water. Once it's full I pull the plug (use tongs or something, that water is HOT). Let it run down the drain and bingo, clean as a whistle. If it's really bad, you might have to do it twice, but I've never had to do it more than that. I had someone put bacon grease down and it was completely blocked with a wad of grease. It only took two applications to clear and it was one of this dinky trailer sinks.
Source: From my great friend and sister, Tracy!
By JodiT from Aurora, CO
Related:
Clearing a Clogged Kitchen Sink Drain