1. Divide the sheet of pastry into two squares of around 8 cm per side.
2. Place the squares in a serving dish: spread half of the sauce onto one square of pastry, cover with half of the strips of burrata cheese and part of the anchovy fillets.
3. Cover with the other square of pastry and repeat the same operation.
4. Decorate the pastry with the remaining anchovy fillets and stalks of chives.