Instructions

1. Unroll or roll out puff pastry to rectangle roughly 25 × 30 cm
2. From short side, roll pastry into tight log like jelly roll; wrap and chill in fridge or freezer 15-30 minutes until firm but not solid
3. Cut log into 12 equal pieces
4. Lightly grease 12-hole muffin tin
5. Place one pastry slice in each hole, cut side up (spiral facing up)
6. Dip thumb in cold water and press from center outward, pushing pastry up sides to form thin cup slightly above rim
7. Chill lined tin while making custard
8. Put milk, cinnamon stick, lemon zest, and pinch of salt in saucepan
9. Heat gently until it just comes to bare simmer, then turn off heat
10. Cover and let infuse 10-15 minutes; remove cinnamon stick and zest
11. In bowl, whisk together egg yolks, whole egg, sugar, and flour until smooth paste with no lumps; add vanilla extract if using
12. Re-warm infused milk to just hot (do not boil)
13. Slowly pour hot milk into egg mixture in thin stream, whisking constantly to avoid scrambling
14. Return mixture to saucepan
15. Cook over low to medium-low heat, whisking constantly, until it thickens just enough to lightly coat back of spoon and you see little steam
16. Remove from heat and whisk 30 more seconds
17. Strain through fine sieve into jug with spout to remove any lumps or cooked egg bits
18. Cover surface with plastic wrap touching custard and let cool to lukewarm or room temperature
19. Preheat oven to 245-250°C (475-480°F) with rack in middle
20. Take pastry-lined tin from fridge
21. Give custard quick whisk, then pour or spoon into pastry cases, filling about 3/4 full (do not overfill)
22. Bake 15-20 minutes, watching closely from minute 12: pastry should be deep golden and crisp; custard set around edges with gentle wobble in center; tops should have dark brown spots/light scorch marks (not burnt)
23. Cool in tin 5-10 minutes so pastry firms
24. Carefully twist and lift out to wire rack; run small knife around any that stick
25. Serve warm or at room temperature
26. Dust lightly with powdered sugar and small pinch of cinnamon just before serving