Place the rack in the center of the oven. Preheat the oven to 350ºF.

Spray a 9x5-inch loaf pan with nonstick cooking spray. Line the pan with an 8 1/2x15-inch strip of parchment paper so that the ends overhang the long sides.

In a bowl, whisk together the flour, baking powder and salt.

In a small saucepan over medium-low heat, combine the coconut oil and the butter and cook just until melted. Remove from the heat.

Place the eggs and the sugar in the bowl of a stand mixer. Beat until thick and smooth, but not fluffy, about 1 minute. With the mixer on low, beat in the coconut oil mixture just until combined.

Add about 1/3 of the flour mixture to the wet mixture and mix just until combined. Add the remaining dry ingredients in 2 more additions, beating just until combined after each addition. Remove the bowl from the mixer, and using a rubber spatula, fold in the coconut milk, the shredded coconut and the macadamia nuts just until combined - do not overmix.

Bake the loaf for 10 minutes, then reduce the temperature to 325ºF. Bake until a tester inserted in the middle comes out clean, 40 to 50 minutes.

Transfer the pan to a wire rack to cool for 10 minutes. Then grab the parchment paper that is overhanging on the sides to lift the loaf out of the pan. Set the loaf on the cooling rack.

Place the last 1/2 cup of coconut in a small skillet over medium heat. Toast the coconut, stirring continuously with a wooden spoon, until it is golden brown. Pour onto a plate and allow to cool.

In a medium saucepan over medium heat, combine the coconut milk, sugar and coconut extract. Bring to a boil, stirring until the sugar dissolves and the mixture thickens to the consistency of pancake syrup, 4 to 5 minutes.

Use a wooden skewer to poke holes all over the top of the cake. Brush the top and the sides of the loaf with the coconut syrup. Immediately top with the remaining coconut.  Let cool completely before slicing.