Preheat the oven to 200°C.
Mix flour and butter in a food processor until the mixture looks like breadcrumbs.
Add the egg yolk and enough water to bind the pastry together.
Roll the pastry to 0.5cm thickness, cut out two pear shapes, and bake on a tray for 10 minutes.
Simmer wine, water, sugar, and bay leaf in a saucepan and poach the pear halves for 10 minutes.
Combine the goat cheese, chives, and salad onion, then season with salt and pepper.
Stuff the cheese mixture into the pears, place them on the pastry, and bake for another 10 minutes.
Serve the tart on a warm plate garnished with a basil leaf.