My way after years of experience I guess 🤷♂️.
Boil the potjie full with meat off-cuts, bones, handful of salt, loads of onion, and any other left over veg for 1 hr.
Discard contents and repeat the above..
Discard contents.
Clean with no more than a sponge or cloth.
No dishwasher liquid.
After doing this, then:
Option 1. Fire:
Line the inside of the potjie liberally with oil.
Get a big bed of hot coals.
Place potjie on top.
When smoking hot, take off.
Pour any oil out and let cool.
Wipe clean with a cloth.
Add liberal oil layer again.
Put back on fire.
When smoking hot, take off and let cool.
Wipe clean.
Option 2. Oven:
Line the inside of the potjie liberally with oil.
Turn the oven on to max temp (240 DegC).
When at temp, place potjie and lid upside down in the oven.
When really hot (maybe 1 hour), take out.
Wipe clean with a cloth.
Add liberal oil layer again. Put back in the oven.
When hot, take out and let cool. Wipe clean.
It's done!
Just wipe a thin layer of oil on the inside if not using immediately and after every use to prevent rusting.
Easy Peasy 💪😅