In most French patisseries, unsold items such croissant and brioche find their way to reborn into amazing treats. Croissant is turned into almond croissant (croissant aux amandes) and brioche and other viennoiserie into bread pudding. The classic brioche Polonaise is originally made using leftover brioche a tete which are soaked in orange flavored syrup or rum or kirsch, stuffed with pastry cream mixed with fruits confit (Tutti frutti mix diced candied fruit 1/4), and covered with Italian meringue. Here is a polonaise tart version finished with a light marshmallow meringue (marshmallow fluff). Use a 9.5''x6.5''/24x16cm baking tray lined with greased parchment.
Process sugar and almond. Add zest, butter, and salt; cream. Add the egg, flour and baking powder sifted together – mix to combine. Wrap up and chill until firm. Pastry can last a week in the refrigerator or kept frozen for weeks. Since that less than a third of the pastry will be used, Save leftover for more pies or cookies. Take a third of the pastry, work out to soften over a floured work surface and roll out into a thin 0.12’’/3 mm thick sheet. Lay on baking tray lined with greased parchment. Prick dough with a fork and freeze for 20 min. Trim off excess dough and refrigerate or freeze.
Bake pastry for 20 min with pie weights; remove pie weights and bake for an additional 10 min. Set aside.
Bring to a boil and add orange blossom water and alcohol. Use at room temperature.
Soak gelatin in cold water to soften, and drain. Bring milk, one-third sugar and vanilla to a boil. Meanwhile, combine eggs with sugar and starches. Temper egg mixture with hot milk. Pour mixture back into the saucepan and bring to a boil whisking constantly and swiftly. Cook for 2 minutes and blend in gelatin and butter. Spread custard over a frozen baking tray lined with plastic wrap, top with plastic wrap in contact. Cool to room temperature and chill. Beat before using.
Cut brioche into large 1/2''/1.25cm thick slices and trim them off matching the size of the pan. (Avoid small pieces; save scraps for bread pudding). Spread a thin pastry cream layer (with no candied fruits) over the crust. Moisturize generously one side of each brioche slice one at the time, flip and arrange over the crust and pastry cream. Fold candied fruits into the remaining custard and cover the brioche completely. Smooth out and enclose with remaining brioche. Wrap up the cake entirely and flip over another baking tray (crust side up) and freeze for 3 hours. Un-mold, trim edges and cut into 8 bars. Store in the freezer for a couple of hours to harden prior finishing.
Beat egg whites with cream of tartar on medium speed; keep it on foamy stage. Meanwhile, cook sugar and water to 250ºF/121ºC (cuisson au boulé). No need to get fully beaten egg whites before adding syrup. Pour hot syrup in thin stream – increase speed, and beat meringue to firm peaks. Lower speed and continue beating until cool… leave mixer running on low until ready to use.
Cover each (half frozen) bar with a thin coating of Italian meringue. Top with more meringue using a St Honoré pipping tip. Sprinkle some sliver almond. At this juncture, polonaise bars can be kept refrigerated for up to 2 days, or frozen for weeks. Must be partially thawed prior popping up in the oven. This dessert is best being flashed baked than blow-torched. Dust powdered sugar and pop in a 450ºF/230ºC oven for about 6 minutes. Let rest 5 min prior serving – Enjoy!