Make dough: In a stand mixer, add the first 4 ingredients, butter through egg yolk. Cream one minute to combine, scraping the bowl once. Add the 1 1/2 cups of flour and the 1/4 cup dried coconut. Mix to combine. Wrap in plastic wrap, refrigerate 1 hour. (Can be made up to 3 days ahead, let slightly soften before using). Using a 12" false bottomed tart pan, press the dough into the pan with floured fingers until even, and about 1/4" high all around. Refrigerate until cold, about 30 minutes. Remove from the refrigerator, prick all over with a fork. Preheat oven to 350 degrees. Spray a large sheet of heavy foil with oil. Press over dough, oiled side down. Fill with dried beans to weight down. Bake for about 10 minutes. To test, peek under the foil, the dough should be just drying out, but do not let color.
Cool a few minutes, carefully lift the foil. Save the beans if you like, discard the foil.
While crust pre- bakes, make the filling.
In a medium sized bowl, add the next 5 ingredients, butter through sea salt. Cream with a small whisk. Add the flour, slowly mix in. add the heavy cream, set aside.
Wash and dry the plums, Cut each in half, discard the pits. Cut the plums again in half, 4 pieces per plum. Set aside.
Cool the crust completely. Smooth the filling over the crust. Arrange the plums in three rows around, spacing them about 3/4 " apart. Sprinkle 1 T. sugar on top.
Cover the tart with foil, bake in preheated oven for 30 minutes. The tart filling will look set, start to puff up and color. Uncover and bake the tart for 5 more minutes, until done. Watch that the crust does not get too dark.
Make the glaze while the tart bakes. In a small skillet, add the pomegranate juice (or grape juice) and 1 T. honey. Reduce, stirring once at medium heat until reduced to 2 T. Keep a watch on the glaze, not to let it reduce more that 2 T. (If it does, add a drop more juice).
Remove the tart from the oven. Cool on a wire rack. Pour the glaze over and scatter with the chopped almonds. Serve and enjoy, or cover with plastic wrap and foil and serve the next day. Dust the crust with confectioner's sugar if desired.