Coarsely chop the raw, unsalted nut mix of almonds, pecans, and hazelnuts with a sharp knife. At the same time, spoon the full-fat Greek yogurt into a bowl and stir in the drops of stevia or vanilla extract as desired.
Place a skillet on the stove and heat it without adding oil or butter. Briefly toast the pumpkin seeds in the hot, dry pan. Shake the pan regularly to prevent them from burning. Remove the pan from the heat as soon as the seeds start to pop.
Scatter the coarsely chopped nuts and warm toasted pumpkin seeds over the Greek yogurt. Then distribute the Ceylon cinnamon evenly over the bowl to finish.
Serve the dish immediately if you prefer a firm bite and maximum crunchiness. Otherwise, let the ingredients rest in the yogurt for two minutes before eating, so the texture of the nuts and seeds becomes slightly softer.