a doctor whose 'specialty' [=('Brit') 'speciality'] is skin problems
Eggs are my dad's 'specialty'. [=('Brit') 'speciality']
Buttermilk pie is a Southern 'specialty'.
(..) - You said you were a lawyer? - Yes. And the study of clocks is a hobby? This is an obsession. Really my specialty. My practice centres around antiquities. But the origin of this clock completely eludes me. I've never seen anything quite so beautiful that I know so little about. (..)2001 Lara Croft: Tomb Raider