In a stand mixer fitted with a paddle attachment mix together dry ingredients.

Add cold butter, mixing on low until mixture forms pea sized clumps.

Mix egg yolk and milk in a small bowl

While on low speed, slowly stream egg mixture into flour and butter mixture. Mix only for about 15 seconds until dough begins to come together

Dump out onto your counter top and smear with the heel of your hand just about 4 times and then shape into a 6" disc

Cover with plastic wrap and refrigerate for at least 20 minutes (dough can be tightly wrapped and frozen at this stage - thaw overnight in refrigerator when ready to use)

Preheat the oven to 350° and move rack to the centre

Remove crust from refridgerator a few minutes ahead of time or while preparing fruit filling (step 4)

Place disc onto a sheet of parchment paper and roll out to about 14". You want the crust to be fairly thin and you need enough diameter to cover the filling edges

Mix all plums through lemon zest in a large bowl until sugar begins to stick to fruit

Pile fruit into centre of crust and spread to about 2" from edge of crust

Gently fold edges of crust up and around the fruit filling, overlapping as needed

Brush the edges of the crust with a bit of the remaining egg white and sprinkle with coarse sugar if desired. This isn't necessary but it's pretty!

Carefully slide the crust, still on the parchment paper, onto a baking sheet and place into 350° oven on the centre rack for about 55 minutes until crust is nicely golden and filling is juicy.