Preheat the oven to 180C / 355 F. Clean the plums, cut in half, pitted and cut into 1/2-inch wedges. Set aside.
2 1/2 pounds (1200 g) dark plums
Prepare the almond paste. In a small bowl, combine 1/4 cup of the sugar with the ground almonds, flour and rum. Combine well with spatula. Set aside.
3 tablespoons (25 g) ground almonds, 1/4 cup (50 g) sugar, 3 tablespoons (25 g) all-purpose flour, 1 teaspoon rum
Roll out puff pastry into the shape of oval or circle (doesn't need to be precise here, it is artisan galette). Spread the almond paste onto the whole puff pastry. Take the sliced plums and place them in a circular pattern, while leaving the edges of puff pastry free.
1 package (445 g) frozen puff pastry
Place the bits of butter on top of the plums and sprinkle a little from the 1/3 cup of brown sugar over the plums, then fold the edges of the puff pastry. Run the egg-wash on the edges and sprinkle the edges with the remaining brown sugar. Place a few blanched and sliced almonds on the edge of the galette as well. Bake in preheated oven 180 C/ 355 F for 45 minutes.
3 tablespoons (60 g) unsalted butter, 1/3 cup (70 g) brown sugar, 1 small egg, 1/2 cup (35 g) blanched sliced almonds
Take the galette out of the oven and evenly brush apricot jam over the hot fruit and brush some up onto the crust too. Let the galette cool to room temperature before serving.
1/2 cup (150 g) apricot jam