Preheat your oven to 200°C (180°C fan-forced). Line two large baking trays with baking paper.

Lay one sheet of puff pastry flat on a clean surface. Spread a thin, even layer of basil pesto over the entire surface, right to the edges. Sprinkle grated mozzarella or tasty cheese evenly over the pesto layer.

Place the second sheet of puff pastry directly on top of the first, pressing down gently so the layers stick together.

Using a sharp knife or pizza cutter, slice the layered pastry into long strips about 2 cm wide. Each strip will form one tree.

Starting from the top, fold the pastry back and forth (like a ribbon) to create a zigzag 'tree' shape that narrows toward the top. Insert a small skewer or pretzel stick into the base to hold it together and form the 'tree trunk.'

Transfer the shaped trees onto the prepared baking trays. Brush each one lightly with beaten egg for a golden, glossy finish. Sprinkle with sesame or poppy seeds if desired for extra texture and decoration.

Bake for 12–15 minutes, or until puffed and golden brown.

Allow the trees to cool slightly before serving. Serve warm or at room temperature.