Set oven to 350°F (175°C). Prepare two baking trays by lining them with parchment paper and set aside.
Lay thawed filo sheets on a flat surface. Cut into 3 equal portions lengthwise, then halve each crosswise to get 36 squares.
Take one pastry square and place it on a flat surface; use a damp towel to cover the rest. Apply melted butter to the square. At one end, add a brie slice, 1 tsp cranberry sauce, and 1 tsp almond flakes. Roll the pastry and pinch both ends to create a cracker. Do the same with the remaining filo squares.
Move filo crackers onto the prepared baking trays. Coat with the remaining melted butter and scatter black sesame seeds on top. Bake for 15–20 minutes, until golden.
Top with rosemary leaves or chives.