Sweet Shortcrust Pastry

Rub the butter into the flour. Sift the dry ingredients (flour, icing sugar, and salt) into a large bowl. Add the lemon zest and the cold, cubed butter into the flour. Rub the butter and flour together between your fingers until it resembles a breadcrumb consistency with a few pea-sized pieces of butter still visible.
Add egg and water. Make a well in the centre of the flour and pour in your egg. Using a fork, mix the egg into the flour. Add 1 tablespoon (15 ml) ice-cold water and use your hands to bring the dough together. Add more water sparingly if needed.
Bring dough together and refrigerate. Tip the pastry onto a lightly floured work surface. Use floured hands to shape the pastry into a ball, taking care not to overwork the dough. Flatten slightly into a disc and wrap well in cling wrap. Place in refrigerator for at least 1 hour.
Roll out dough. Remove the chilled pastry from the refrigerator and transfer it to a clean, lightly floured surface. Allow the pastry to sit for about 10 minutes to soften slightly. Roll out the pastry to the thickness of a coin (⅛” thick) and into a 12in (30cm) circle.
Prepare dough in tart tin. Flour the base of a 9in (23cm) deep fluted tart tin and gently lift the pastry into the prepared tin. Use your fingers to push the pastry onto the sides of the tin and into the grooves. Trim off the excess pastry from the tin. Refrigerate the prepared pastry shell for at least 1 hour to allow the pastry to relax and the butter to harden.
Blind bake. Preheat your oven to 180°C (350°F). Once the pastry is chilled, prick the base all over with a fork, then line with greaseproof paper and fill with pie weights or rice. Blind bake for 15 minutes, then remove the greaseproof paper and pie weights. Whisk together the egg and milk for the egg wash. Brush the base of the pastry with egg wash and return to the oven for a further 7-10 minutes or until the base is dry and lightly golden. Remove from the oven and leave to cool.
Frangipane Filling

Make frangipane filling. In the bowl of an electric mixer fitted with the paddle attachment, cream the butter, sugar, and lemon zest together on medium speed for 5 minutes until pale.
Add wet then dry ingredients. Add the eggs one at a time, beating between each addition and scraping down the sides of the bowl. Add the almond meal, flour, salt, vanilla, and almond extract and mix until combined. Pour the frangipane filling into the tart shell and spread out evenly.
Slice plums and place on tart. Cut each of the plums in half and remove the stones. Thinly slice the halves. Starting from the outside and working your way in, place your plum slices next to one another, spiraling in on top of the filling. Place the tart back in the oven and bake for 45 minutes, until the filling has set and is golden brown.
To Decorate

Remove the tart from the oven and brush the plums with honey warmed in the microwave for a couple of seconds. Sprinkle with thyme leaves (optional but recommended).