Start by poaching the squash: place it in a pan and cover with cold water. Add a generous pinch of salt and place the pan on a medium heat. When the water comes to a simmer, turn down the heat to low and cook gently until the squash is just tender but still firm. Drain and set aside.

Now grill the beef: rub the meat with the fish sauce and sprinkle with the caster sugar. Preheat a BBQ or griddle pan, grill the steak to rare / medium rare. Set aside to rest for 5 minutes, before slicing into bite-sized chunks against the grain.

To cook the curry: Take two tablespoons of the thick coconut milk from the top of the tin and add it to a pan with the coconut oil. Turn the heat to medium and allow the cream to boil for a minute and become oily. Now turn the heat to medium-low and add the curry paste, fry slowly in the oily cream for 4 - 5 minutes, stirring regularly, until very slightly darkened and aromatic, and the oil rises to the surface.

Next, stir in your palm sugar and cook for another minute before adding the fish sauce. Cook for 30 more seconds before adding the stock, remaining thick coconut milk, plus 5 tablespoons of the thinner milk from the bottom of the can (discard the rest, or keep it for another recipe), the stock, and torn lime leaves (if using). Simmer this gently for 1 - 2 minutes.

Add the butternut squash and simmer for 2 more minutes, before stirring in the sliced chilli, cooked and sliced beef, and the picked Thai basil leaves. Turn off the heat and serve.

Eat with jasmine rice (and ideally with one or two other Thai dishes, to make a balanced Thai-style meal).