Heat your oven to 160C fan/gas mark 4. Line a 2lb (21cm * 11cm * 7cm) with a sheet of baking paper.
Place the milk, honey and butter in a small pan and heat gently until the butter has melted. In the meantime, mix the rest of the ingredients apart from the eggs, in a large bowl.
Pour in the melted butter mixture and use a large spoon to stir until just combined. Add the eggs and stir again until fully combined.
Transfer to the baking tin, top with the 50g of macadamia nuts and sprinkle with the demerara sugar. Bake in the centre of the oven for 30 minutes.
Open the oven and rotate the cake for an even bake, then leave for a further 20-25 minutes. It should feel lovely and bouncy when you press it.