01 - Combine bread flour, yeast, sugar, and salt in a large bowl. Add warm water and olive oil, mixing until a rough dough forms.
02 - Knead the dough on a lightly floured surface for 8 to 10 minutes until smooth and elastic.
03 - Place dough in a lightly oiled bowl, cover, and let rise in a warm spot until doubled in size, approximately 1 hour.
04 - Combine cottage cheese, chopped spinach, Parmesan, black pepper, and nutmeg in a bowl. Mix thoroughly and set aside.
05 - Preheat oven to 425°F and line a baking sheet with parchment paper.
06 - Punch down the risen dough and divide into 8 equal pieces.
07 - Flatten each piece into a 5-inch circle. Place 2 tablespoons of filling in the center of each circle, then pinch edges together to seal completely.
08 - Flip each filled dough ball seam-side down. Gently flatten with your palm to form a 1-inch thick disc. Poke a 1-inch hole in the center using your finger to create the flagel shape.
09 - Place flagels on the prepared baking sheet. Brush tops with beaten egg and sprinkle with seeds if desired.
10 - Bake for 18 to 20 minutes until golden brown and cooked through.
11 - Cool slightly on a wire rack before serving warm.