Preheat your oven to 180°C (350°F) and lightly grease a mini muffin tin to prevent sticking.
Roll out the thawed puff pastry on a lightly floured surface, gently pressing with a rolling pin to smooth it out. Use a sharp knife or pizza cutter to cut the pastry into 24 neat squares, about 3x3 inches each.
Press each pastry square into a muffin cup, gently shaping the edges to form small cups. Chill the tray in the fridge for a few minutes to help the pastry hold its shape.
Place a small piece of Brie (about half a teaspoon) in the center of each pastry cup, pressing slightly to set it in place.
Add a teaspoon of cranberries on top of each piece of Brie, distributing them evenly across all cups.
Brush the edges of the pastry with beaten egg to give a golden, shiny finish when baked.
Bake the bites in the preheated oven for 15-20 minutes, or until the pastry is puffed and golden brown, and the Brie is melted and bubbling.
Remove the tray from the oven and let the bites cool in the tin for about 5 minutes, then carefully transfer them to a cooling rack to cool slightly.
If desired, drizzle a small amount of honey or glaze over each bite for added shine and sweetness.
Serve the cranberry Brie bites warm or at room temperature, arranged on a platter, and enjoy their flaky, gooey, and tart flavors.