First, add the butter to a small saucepan on medium heat. Make sure to continuously stir or swirl the pan as the butter melts and then froths. When you see the milk solids turn a light brown color, turn off the stove and move the pan from the heat. The butter will continue to cook and should end up a nice warm brown. Let it cool just enough to pour into a small bowl or container and place the browned butter in the refrigerator to re-harden for about 30 minutes. You don't want it to completely harden just go opaque and start to thicken at the edges.
Next, turn on the oven to 275°F (135°C) and add your macadamia nuts to a baking sheet. once the oven comes to temperature, bake them in the oven for about 5 minutes. While the nuts are in the oven, prep the white chocolate by giving both bars a rough chop and setting them aside. After the macadamia nuts have been taken out of the oven and cooled, give them a rough chop and set them aside as well.
Once the toppings are prepped, combine the flour, baking soda, and salt together in a small bowl.
In the bowl of a stand mixer with whisk attachment, add in the granulated sugar and egg plus one egg yolk. Turn the mixer to medium speed until the egg and sugar start to lighten considerably in color, about 2-3 minutes. Next, add in the vanilla extract, almond extract, lemon zest, and lemon juice. Let the mixer continue for another 1-2 minutes until the ingredients become homogeneous and all of the granulated sugar has dissolved.
Turn down the mixer to low and whisk in the cooled browned butter and brown sugar. Once that just comes together, turn off the mixer and scrape down the sides of the bowl. Turn it back on low and add in the flour mixture. Shut off the machine as soon as everything comes together. Do not overmix.
Now you can fold the toppings into the dough. Once that is complete, grab a #24, 2in (5cm) cookie scoop (it should hold roughly 2.5tbsp or 50g of dough) and scoop cookies onto a silicone lined baking tray. Cover the cookies with cling wrap and make sure to seal the wrap to the sides of the tray. You want to keep as much air from the dough as possible. Refrigerate for at least 6 hours and up to 24 hours.
After resting the dough, preheat your oven to 350°F (177°C) and add the pre-scooped cookies to a silicone mat lined baking sheet with at least 2in (5cm) of space between them. Bake for 15-16 minutes. The edges of the cookies should just start to brown and the middle should be completely puffed and not look wet. Let cool for 5 minutes before moving to a cooling rack.