Whisk together the flour, salt, and sugar. Add in butter and use a fork or a pastry cutter to mix in the butter under the mixture resembles a coarse meal. You can also use a food processor, but I just rarely do. I love the feel of pastry!

Slowly add in ice water until the dough starts coming together. Make sure it is not too crumbly or dry. It's okay if there are still some larger bits of butter remaining.

Form dough into a ball, wrap in plastic, and refrigerate for at least an hour.

Roll out the dough on a floured surface. This is a rustic tart, and this does not need to be perfect. Just make sure it is about a quarter of an inch thick. Transfer to a parchment lined baking sheet.

Preheat oven to 350 degrees. Then whisk together the vanilla sugar and the almond meal. Sprinkle half of that mixture onto the rolled out dough, then arrange the sliced plums on top, leaving a border for you to be able to fold over the dough. Top with remaining almond and vanilla sugar mixture, crimp the crust and chill for 15-30 minutes.

Brush the crust with coconut milk and bake the galette for about 35 minutes until the pastry golden-brown and the plums are plump and juicy.