1. Preheat the oven to 200°C (400°F).
2. In a large skillet, heat the olive oil and sauté the sliced leeks. Season them, but be careful not to add too much salt as the sausages are already very salty.
3. When the leeks are halfway cooked, add the sliced sausages (it is more convenient to cut them with scissors).
4. Towards the end of the cooking time, add the fresh cheese (still on the heat).
5. Let it melt while stirring, then sprinkle with Parmesan or grated cheese.
6. Let it melt again while stirring, and soften the mixture with a little fresh cream.
7. Unroll the pastry in a tart pan. Beat the two eggs in a bowl and add the fresh cream.
8. Spread the leek/sausage mixture on the bottom of the pastry, then pour the egg/cream mixture over it.
9. Bake for about 30 minutes at 200°C (400°F).