Preheat oven to 180°C fan forced. Line a large baking tray with baking paper. Heat 1 tablespoon of the oil and half the butter in a large non-stick frying pan over medium heat. Add the leek and garlic, and cook, stirring, for 3-4 minutes or until the leek is soft and lightly golden. Add the spinach and cook, stirring, for 1-2 minutes or until just wilts. Remove from heat and drain any excess liquid.
PREPARE THE PARCELS
Melt remaining oil and butter in a small dish in the microwave for 20 seconds on high. Place one sheet of filo on a clean work surface. Brush lightly with the oil mixture. Top with another sheet. Fold in half crossways. Repeat with the remaining pastry sheets and oil mixture.
FILL THE PARCELS
Divide the leek and spinach mixture among the pastry rectangles. Top with a piece of salmon. Spoon 1 tablespoon of pesto onto each piece of salmon. Bring the long pastry edges together and fold to create a seam. Tuck ends in to create a parcel. Place on the lined tray. Brush the pastry with the remaining oil mixture.
BAKE
Bake for 20-25 minutes or until puffed and golden. Serve with mixed salad.
