Just cleaned my pan last week
Old-timer told me about this a while back. Second year doing it so I thought I'd post.
Last boil of the year I left a pretty thick pan behind. Filled it with water about 5" deep and let it sit........until July.
Drained it and washed it out with fresh water and a sponge. No real scrubbing needed. The moldy, nasty, smelly goo in the pan cleans almost all the niter and crud off leaving a nice shiny pan behind.
I highly recommend it.
1980 - 6 taps, stone fire pit, drain pan evaporator, 1 pint of syrup
2016 - 55 taps on 3/16 and gravity, new sugar shack, 2x3 Mason XL, 16 gallons of syrup
2017 - 170 taps on 3/16, 2x4 Mason XL, NextGen RO. 50 gallons of syrup
2018 - 250+ taps on gravity and buckets, 2x5 Smokey Lake arch and Beaverland pan.
2019 - 250+ taps on gravity. A few buckets. 35 gallons of syrup.
2020 - 300+ taps on gravity. 50 gallons of syrup.
2021 - 280 taps on gravity and 40 buckets. 35 gallons of syrup.