Put the spinach in 50 ml boiling water, cover and cook for 7-9 minutes. Pour into a sieve and drain well. In the meantime thaw puff pastry at room temperature for about 15 minutes.
Peel and finely chop the onion. Peel garlic and chop finely. Heat oil in a pan and crumble minced meat into it. Fry well all around. Add onion and garlic and fry briefly.
Add tomato paste and mix well. Add tomatoes, bring to the boil and season to taste with salt, pepper, paprika and sugar. Let simmer for about 4 minutes. Roll out the puff pastry on a lightly floured work surface.
Place in a lightly greased casserole dish (allow the rim to protrude slightly). Sprinkle with breadcrumbs. Fold the spinach into the mince. Pour onto the puff pastry. Crumble feta cheese on top.
Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 15 minutes. Remove from the oven and serve garnished with parsley as desired.