Filling:
About 6 cups loosely packed fresh stinging nettle
3 tbsp. high quality butter
1 small sweet onion, chopped
1-2 cloves garlic, minced
1 egg
1/4 cup plain whole milk Greek yogurt
1/4 cup or more crumbled feta cheese
sea salt and pepper
Rinse nettles. Drain on a kitchen towel and pat dry. Working in batches, pulse nettles in a food processor until coarsely chopped. Transfer to a bowl.
Place butter in a large skillet over medium heat. Add onion and saute until clear and aromatic, 3 minutes. Add garlic and saute another 2 minutes. Add nettles and a splash of water. Saute for about 5 minutes until nettles are fully wilted but still bright green. Season lightly with sea salt and pepper.
Transfer to a bowl and cool completely.
Add remaining ingredients and blend thoroughly with a rubber spatula.
Pastry Dough:
1 1/4 cup quality all-purpose flour
1 tsp. sea salt
1 stick high quality unsalted butter
3-4 tbsp. ice water
Preheat oven to 375.
Place flour and salt in a food processor. Pulse. Add the butter and blend until it resembles a course meal. Slowly pour in the ice water with blade running until dough forms.
Turn out onto a floured work surface. Form dough into a disk and wrap in parchment. Chill for 15 minutes.
Return dough to work surface. Roll disk out with a rolling pin to about 1/4 inch thickness, keeping circular shape.
Evenly spread nettle filling over pasty. Using a pizza cutter or sharp knife, cut approximately 12 pie-shaped wedges in dough.
Starting with the wide end, gently roll each wedge toward its tip. Transfer to a parchment lined baking sheet, allowing an inch of space between each rugelach.
In a small bowl, whisk one egg yolk with a splash of cold water. Brush egg wash over pastry dough.
Bake for about 30-40 minutes or until golden brown. Serve warm.
