I heated up some tomato soup for dinner the other night and while distracted the pot boiled over a bit, spilling tomato soup down the sides of the pot. Seeing the bright copper stripes where the tomato soup had spilled reminded me of how long it had been since I’d cleaned off the bottoms of the pans with something acidic enough to show the copper!
I started to think about buying some “copper cleaner” and then remembered I didn’t need to buy anything. Basically just lemon juice, salt and flour to make a paste. Worked great!
I forgot to take before and after pictures but trust me, the pots look great now! And I think they conduct the heat better when clean.