Pain aux Raisins Muffins

Prepare Custard

1. In a medium saucepan, whisk together the milk, granulated sugar, egg yolks, and cornstarch until smooth. Cook over medium heat, stirring constantly, until the mixture thickens to a custard consistency. Remove from heat and stir in the vanilla extract and cinnamon.
2. Transfer the custard to a bowl, cover with plastic wrap pressed directly onto the surface to prevent a skin from forming, and chill in the refrigerator until completely cool (about 30 minutes to 1 hour).

Assemble Muffins

1. Preheat your oven to 400°F (200°C). Lightly grease a 12-cup muffin tin.
2. On a lightly floured surface, roll out the puff pastry sheet into a 12x16 inch rectangle.
3. Spread the cooled custard evenly over the puff pastry, leaving a small border around the edges. Sprinkle the drained raisins over the custard.
4. Starting from one long side, tightly roll up the pastry into a log.
5. Slice the log into 12 equal pieces, approximately 1 inch thick.
6. Place each slice cut-side up into the prepared muffin tin cups.
7. In a small bowl, whisk together the egg and water for an egg wash. Lightly brush the tops of the muffins with the egg wash.

Bake

1. Bake for 18-20 minutes, or until the muffins are golden brown and puffed up.
2. Remove from the oven and let cool slightly in the muffin tin before transferring to a wire rack to cool completely. Serve warm or at room temperature.