Defrost spinach at room temperature. In the meantime prepare the pie dough and put it in a cool place.
For the filling, peel and finely dice or chop the onions and garlic. Heat the oil in a large pan. Fry the minced meat in it until crumbly. Fry the onions and garlic briefly. Squeeze out the spinach in portions and add.
Stir in the tomato paste. Season to taste with salt, pepper and nutmeg. Let the filling cool down for about 15 minutes. Roughly dice cheese and fold in.
Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). For the base, roll out a good half of the dough and line a greased pie dish (26 cm Ø) with it. Distribute the filling evenly in the mould.
Roll out the rest of the dough as a lid and cut out stars. Place the dough on the filling using the baking paper. Carefully remove the baking paper. Press the dough base and lid together.
Decorate the border with a garland pattern (see page 73). Whisk the egg yolk and milk, spread a thin layer on the surface. Spread the stars on it and also brush it on. Bake the pie in a hot oven for about 50 minutes.