Preheat the oven to 350°F (175°C) or heat a dry skillet over medium heat — you’ll be toasting everything to bring out the oils and aroma.
Spread the Hazelnuts on a baking sheet and toast in the oven for 8–10 minutes (or in the skillet, turning frequently) until fragrant and the skins begin to blister; wrap in a clean towel and rub to remove most of the loose skins, then let cool.
Toast the Sesame Seeds in a dry skillet over medium heat, stirring constantly, until they turn golden and smell nutty — watch them closely so they don’t burn; transfer to a bowl to cool.
In the same skillet, toast the Coriander Seeds, Cumin Seeds and Black Peppercorns for 1–2 minutes until fragrant, then remove from the heat and let them cool slightly.
Coarsely grind the toasted spices (coriander, cumin and pepper) in a spice grinder or mortar and pestle — you want a coarse texture, not a powder.
Pulse the cooled hazelnuts and sesame seeds in a food processor a few times until they form a crumbly mixture with some larger pieces remaining; combine with the ground spices and taste for balance.
Season to taste with Sea Salt, pulsing once or twice to distribute it evenly. Adjust salt and spice proportions as desired.
Let the dukkah cool completely, then transfer to an airtight jar. Serve with good olive oil and warm bread for dipping, or sprinkle over salads, roasted vegetables or grilled fish. Store in a cool, dry place for several weeks.
