I tried using dish soap to clean it off, but the grease was thick and sticky and wouldn’t come off easily. I didn’t want to soak it, because I wasn’t sure whether it was okay to soak the heating element on the bottom of the kettle. Then I tried multipurpose cleaner, but it hardly made a dent.
Here’s what worked. I put some Goo Gone on a paper towel and wiped off most of the grease, reapplying Goo Gone to the paper towel occasionally. Then I put a little dish soap on a paper towel with a little water and wiped the kettle down to remove the oily Goo Gone. Finally, I took a damp paper towel and cleaned off the last of the residue from the Goo Gone and the soap. Not the greenest method, I know, but it worked! I was very careful near the mouth of the kettle not to get any Goo Gone inside.
I've only cleaned the kettle this thoroughly once. Since we don't keep it near the stove anymore, it just needs to be wiped down occasionally.
Thanks for reading!