This is a rustic tart with an unsweetened dough. The recipe is originally from Jacques Pepin and is hard to improve on. Do not peel the pluots, as their skins add tartness and color to the pastry.
For the dough: Dice 3/4 C. cold butter into small cubes. Add to a food processor with 3/4 C. all-purpose flour. Process for 5 seconds. Drizzle in 2 T. ice water and process another 5 seconds, until the dough barely comes together.
Gather the dough into a ball and then roll it out in a 8″ inch circle. Transfer it to a baking sheet or pie pan and refrigerate for half an hour.
Preheat the oven to 400.
For the filling: Combine 2 T. granulated sugar with 1 1/2 T. all-purpose flour and 1 1/2 T. ground almonds. Spread this evenly over the dough but leave a 1″ circle all the way around.
Cut 1 lb. pluots into not-too-thick slices, removing the pits. Arrange the slices atop the sugar/flour/almond mixture. Cut 1 1/2 T. cold butter into small pieces and arrange over the top, then sprinkle with 1 T. more sugar. Fold the edge of the dough up over the fruit, then sprinkle the edge with a little more sugar.
Bake the galette for 1 hour. The crust should be crisp and golden.