Prick the pastry thoroughly all over with a fork and cut out into 4 x 14-15cm circles. Lay them into individual tart 9-10cm x 2-3cm deep tart tins, pushing them into the corners before trimming the tops neatly with a sharp knife. Fill them with discs of greaseproof paper or foil, add baking beans to anchor the paper and rest for 15 minutes in the fridge.
Pre-heat the oven to 180°C/gas mark 5. Bake the tart cases for 10-15 minutes until they begin to colour, then remove from the oven and leave to cool for a few minutes.
Meanwhile put the cream and saffron into a small saucepan and bring to the boil. Remove from the heat and leave to infuse for about 10 minutes.
In a bowl, mix the egg yolks, sugar and cornflour together, then pour the cream on to the egg mixture and mix well with a whisk. Return to the pan and cook gently over a low heat for a few minutes, stirring constantly with a wooden spoon until the custard thickens. Don’t let it boil.
Remove from the heat, give a mix with a whisk pour into the tart cases and bake for 10-12 minutes until set. Leave to cool a little and remove from the moulds by loosening with a small knife. Serve warm or cold.