I have never cooked on a flower pot but Brisket is Brisket.
Trim all the hard fat
Thin the fat cap to 1/4"
Apply your rub I like 50/50 k salt & black pepper
Get the cooker to 300
Fat cap down
After 4 hrs wrap the brisket in a single layer of Butcher Paper
and go back on fat cap up
after 1.5 hrs start checking the flat for probe tender(hse a parring knife and make a small hole to probe through)
once the flat is probe tender put the brisket on a sheet pan and sit it on the counter top, Put a thermo in the flat when the IT drops to 150 it is ready to carve
I never met a Cow that I didn't like with a little Salt & Pepper! Certified PORK-A-HOLIC