2.Place beef and flour in a large bowl; season. Toss to coat beef evenly in flour, shaking off excess. Heat oil in large flameproof roasting pan over medium-high heat. Cook beef for 3 minutes on each side or until browned all over; transfer to a large heatproof bowl or tray.
3.Add onion and garlic to same pan; cook, stirring, for 5 minutes. Add curry paste; cook, stirring, for 1 minute. Add coconut milk and stock; stir to combine.
4.Return beef to pan. Cover with one sheet of baking paper and two sheets of foil; wrap tightly to seal. Transfer to oven; bake for 3½ hours or until beef is tender.
5.Serve half the massaman beef topped with peanuts. Transfer remaining massaman beef to an airtight container; cool, then store.
Serve with chilli-garlic broccolini and, if you like, steamed rice.
Refrigerate massaman beef in an airtight container for up to 3 days. Freeze for up to 3 months; thaw in the fridge, then reheat in a microwave.