How ‘Breaking Bad’ cooked up the addictive formula for ‘Better Call Saul’

By spawning the acclaimed “Better Call Saul,” “Breaking Bad” achieved a bit of spinoff immortality that eluded “Friends” (“Joey”), “MASH” (“AfterMASH”) and “The Golden Girls” (“The Golden Palace”), among others. As the prequel nears its end, it’s worth considering how the original series’ Emmy-winning legacy cooked up one of the best TV offshoots since “Cheers” begat “Frasier.”