Rinse the apple, remove the core, and cut the fruit into cubes. The skin doesn't need to be removed. Coarsely chop the macadamia nuts with a knife and set aside.
Heat the coconut oil in a small frying pan. Add the apple cubes and cinnamon. Cook this mixture for about five minutes over medium-high heat until the apple is soft. At the same time, use a second, dry frying pan to toast the coarsely chopped macadamia nuts. Heat the nuts without oil until they take on a light color.
Remove both pans from the heat once the apple is soft and the nuts are colored. Stir the apple cubes one more time so the cinnamon is evenly distributed, and shake the nuts briefly in the pan to prevent burning from residual heat.
Divide the Greek yogurt between two bowls. Scoop the warm apple cubes directly from the pan onto the yogurt. Finally, sprinkle the toasted macadamia nuts on top to finish.