The base of all Thai curries and many desserts — the difference between coconut milk and cream, and how they're used.
Coconut cream is the thick, rich first pressing of coconut flesh — used to fry curry paste; coconut milk is the thinner subsequent pressing — used for the curry body.
Authentic Thai curries start by frying the curry paste in coconut cream until it 'splits' (oil separates from solids) — this develops flavour that just simmering doesn't achieve.
Fresh coconut milk squeezed from grated coconut has a different, more nuanced flavour — available at markets; tinned is consistent and convenient.
Salted coconut cream drizzled over mango sticky rice, sweet coconut milk in dessert soups, coconut cream in khanom krok — coconut is the defining dessert flavour.
Or Tor Kor Market and major wet markets sell freshly pressed coconut milk by the bag — buy only what you'll use within a day.