Larry, as a home brewer I use a lot of Oxyclean to clean heavy crud, use hot water and full scoop per about 3 gallons, let it sit for hours or even overnight.
If you want an even stronger solution, mix 1/3 TSP substitute with 2/3 Oxy, and same as above.
It will lift hard burnt items off a pot , like burnt Rice even.
Cheap and effective for most things, and probably worth a try.