01 - Preheat your oven to 400°F. Line a baking tray with parchment paper.
02 - Heat olive oil in a skillet over medium heat. Add the spring onions and garlic; sauté for 1–2 minutes until fragrant.
03 - Add spinach and cook until wilted (if using fresh) or heated through (if using frozen). Remove from heat and let cool for a few minutes.
04 - In a bowl, combine crumbled feta, cream cheese, cooked spinach mixture, nutmeg, salt, and pepper. Mix well.
05 - Unroll the puff pastry sheet on a lightly floured surface. Spread the spinach and feta mixture evenly over the pastry, leaving a 1/2 inch border along one long edge.
06 - Starting from the opposite long edge, tightly roll up the pastry like a jelly roll. Brush the border with a little beaten egg to seal.
07 - Slice the roll into 16 equal pieces. Arrange pinwheels cut-side up on the prepared tray, spacing them slightly apart.
08 - Brush the tops with beaten egg and sprinkle with sesame or nigella seeds, if desired.
09 - Bake for 18–20 minutes or until puffed and golden brown.
10 - Let cool slightly before serving warm or at room temperature.