1. Snap the stalks from the asparagus. Trim the leeks, cutting them first in half horizontally, then into quarters along their length. Blanch in boiling, salted water for 2-3 minutes until just cooked. Drain through a colander and run under cold water to stop the cooking process. Cut the asparagus in half, then leave, along with the leeks, to dry out on kitchen towel (very important step or your pastry will be soggy).
2. Preheat the oven to 190 degrees and place a baking sheet in the oven to heat up.
3. Unroll the pastry sheet, cut into 4 equal sized rectangles and place onto a piece of baking parchment. Using the point of a sharp knife, score a 2cm border around each. Prick the middle with a fork, brush the border with one of the egg yolks and slide onto the preheated baking sheet. Cook for 10-15 minutes until golden brown.
4. Meanwhile, make the tart filling. Put the whole egg and remaining egg yolk into a bowl and beat gently. Slowly add the goat's cheese and beat until smooth, before adding the cheddar to bring it all together. Season generously.
5. Remove the pastry cases from the oven and spread out the cheese mixture equally in the centre of each tart (the edges should have risen, if they haven't, help them along by cutting along the scored line).
6. Fill the tarts with leeks, running horizontally along the pastry. Then arrange the asparagus on top, with the tips facing alternate directions. Scatter on the flaked almonds, drizzle with olive oil and season again.
7. Bake for another 10-15 minutes until the kitchen smells excellent and the vegetables are just starting to brown.
8. Leave to cool slightly before scattering with dill and serving to very grateful lunch guests with a green salad.