Heat the oven to 300°F. Line a jellyroll pan with foil and spray or brush lightly with olive oil.
Grind the rosemary, salt, fennel, and pepper in a spice mill to a fine powder, or mince the rosemary and grind the mixture in a mortar and pestle. In a large bowl, whisk the egg whites until they foam. Add the spices and cheese. Whisk again to combine. Add the nuts, stirring and tossing to thoroughly coat them. Spread them in a single layer on the foil-lined pan. Bake for 45 min., stirring every 15 min. to redistribute the coating. The nuts will stick to the foil at first and need to be gently pried loose to expose them evenly to the heat. Slide the nuts, on the foil, onto a rack to cool.
Store in screw-top jars or airtight tins; plastic may cause the crisp coating to soften.
nutrition information (per serving):
per 1/4 cup;
Photo: Scott Phillips