One of my friends and his wife ran a very popular food wagon in Houston for over 20 years. They would sell out of brisket every single day, 5 days a week.

Here is what Reuben did;

Rub 20 huge flats with salt and peeper.
Fire smoker to 275f.
Place 20 flats in smoker fat up.
Maintain 250 to 275f for 6 hours.
Turn fat side down.
Maintain heat at 200-250f for 6-7 hours.
Remove from heat and wrap with heavy foil, WHILE HOT.
Cool for 3 hours.
Place in freezer, for at least 24hours.
Thaw as needed and warm on grill.

Their biggest seller was a brisket stuffed baked potato.