Savory Onion and Anchovy Pie

Method

1. Slice the onions (about 1 kg).
2. Melt butter in a large pan over medium heat.
3. Add the sliced onions, bay leaves, and a pinch of salt. Reduce heat to low and cook slowly for at least 40 minutes, stirring occasionally, until the onions become creamy and soft. If they start to stick, add a little water.
4. Remove the bay leaves.
5. Roll out puff pastry into a tart pan with removable bottom, lining the sides. Trim excess pastry.
6. Prick the bottom with a fork.
7. Arrange anchovy fillets over the bottom (to taste).
8. Spread the cooked onions evenly on top of the anchovies.
9. Season with black pepper.
10. Cover with a second sheet of puff pastry cut into strips to create a lattice top, or place a full sheet and cut vents for steam.
11. Brush the top with beaten egg.
12. Bake in a preheated static oven at 200°C (400°F) for 35-40 minutes. If the top browns too quickly, cover with aluminum foil.
13. Let cool completely before serving.