Preheat the oven to 200°C (390°F).
Prepare the pizza dough according to your recipe and let it rise until doubled.
Cut the mozzarella into small cubes.
Divide the dough into small balls (approx. 25–30 pieces). Flatten slightly, place a cheese cube in the center, and pinch closed.
Close the bread package and put the closure on the bottom, against the surface.
Arrange the dough balls on a parchment-lined tray in a tree shape (or your chosen shape).
Cover loosely and let it rise for 20–30 minutes.
Whisk the egg with milk or water, then brush over each ball for a golden crust.
Bake for 20–25 minutes until golden, and the cheese is melted.
Brush the warm bread with melted herb butter and sprinkle Parmesan on top.
Serve immediately, pull apart, and enjoy!