'slowly-produced' originates from the combination of 'slowly' and 'produce,' where 'slowly' means 'at a slow pace' and 'produce' means 'to create or bring into existence.'

'Slowly' and 'produce' have been used in English since the Middle Ages, and their combination into 'slowly-produced' reflects a modern usage to describe the pace of production.

Initially, 'slowly' and 'produce' were used separately, but their combination into 'slowly-produced' emphasizes the gradual nature of production.