Let’s dive into the steps that will bring your cruffins to life:

1. Preheat your oven to 375°F (190°C) and grease a muffin tin or line it with muffin liners.
2. In a medium saucepan, combine the diced peaches, granulated sugar, cornstarch, cinnamon, lemon juice, and vanilla extract. Cook over medium heat, stirring occasionally, until the mixture thickens and the peaches soften, about 10 minutes. Set aside to cool.
3. On a lightly floured surface, roll out one sheet of puff pastry to smooth the folds. Brush with melted butter and sprinkle evenly with brown sugar.
4. Spread half of the peach mixture over the puff pastry, leaving a small border around the edges.
5. Starting from one side, roll the pastry tightly into a log. Cut the log into 6 equal pieces.
6. Place each piece, cut side up, into the prepared muffin tin. Repeat the process with the second sheet of puff pastry and the remaining peach mixture.
7. Brush the tops of each cruffin with the beaten egg for a golden finish.
8. Bake in the preheated oven for 25-30 minutes, or until the cruffins are puffed and golden brown.
9. Allow them to cool slightly before dusting with powdered sugar, if desired.

Remember, the aroma that fills your kitchen as these cruffins bake is just as delightful as the taste.