Grind the macadamia nuts in a food processor or blender until creamy, but leaving a few very small chunks.
Mix vanilla extract with the nut butter.
Chocolate:
Melt the cacao butter over a double boiler until it reaches 122°F/50°C.
Add the cacao powder and stir to combine.
Add the honey and ground vanilla and mix until all combined and the mixture reaches 122°F/50°C.
Pour a small amount of the chocolate on the bottom of the mold and freeze for about 10 minutes.
Remove cups from freezer and add a full teaspoon of macadamia nut butter. Roll the macadamia nut butter into a ball and flatten it with your hands, then place it on top of the chocolate.
Cover with the remaining chocolate and freeze or refrigerate before serving.
Notes
To make the nut butter cups I used a silicone mold, but you can also use paper molds.