Small olive green brown glazed pottery bowl leaf design signed N B 4.25 inches

Beautiful little pottery bowl with olive green and brown glaze and what looks like a leaf on one side. It appears to be marked on the bottom with the initials N B but I don't know anything about who made it and when. Measures 4.25" across and about 2" deep. I don't see any defects. Smoke- and pet-free home.