- Pre-heat your oven to 190ºC / 375ºF.
- Roll out the pastry on a lightly-floured surface and use to line 8 individual flan tins.
- Beat the cheese, milk and eggs. Stir in the chives and lightly season.
- Drain the mackerel and flake. Divide among the flan cases and spoon the cheese mixture into each of them.
- Season with ground black pepper.
- Cook for 25 minutes until filling is set.
- Gently release the sides of tartlets and pop them onto a wire tray to cool slightly.