Instructions

1. Make the dough: In the bowl of a stand mixer, combine the flour, sugar, and salt. Add the butter and mix until incorporated. Add the egg yolks and wine and mix until a dough forms. Replace the paddle with a dough hook and knead dough on medium speed until smooth, 5-6 minutes. Form dough into a ball and wrap in plastic; set aside to rest for 30 minutes.
2. Make the fillings: Heat the apricots, poppy seeds, 1⁄2 cup wine, 1⁄2 cup sugar, and 1⁄3 cup jam over medium heat and cook, stirring, until hot, 4 minutes. Transfer the poppy seed filling to a small bowl; set aside. Heat the remaining jam, cinnamon, cloves, and apples in a small saucepan over medium high heat and cook, stirring, until apples soften, 8-10 minutes. Transfer the apple filling to a small bowl; set aside. Heat the remaining wine, 6 tbsp. sugar, walnuts, and chocolate over medium heat and cook, stirring, until smooth, 2-3 minutes. Transfer the walnut filling to a small bowl; set aside. Heat the prunes and 1 1⁄2 cups water in a small saucepan over medium-high heat and cook, stirring, until the prunes are soft and water is almost evaporated, 16-18 minutes. Add the remaining sugar and mash with a wooden spoon until smooth. Transfer the prune butter to a small bowl; set aside. Stir the lemon juice into the poppy seed filling; divide the lemon zest between all 4 fillings, stirring to incorporate.
3. Heat oven to 350°. Line an 8" square baking pan with 2 overlapping sheets of parchment paper cut to 10" x 8". Divide the dough into thirds; set 1 third aside. Cut 2 dough pieces in half and set aside. Transfer the third dough piece to a floured work surface and roll to 1⁄8" thickness. Line the bottom and sides of the baking pan with dough and let excess dough hang over the edges; trim dough to within 1" of pan and brush with butter. Transfer the poppy seed filling to the bottom layer of dough and smooth the top with spatula. Roll 1 piece of the remaining dough to 1⁄8" thickness and trim to make an 8″ square; top the poppy seed filling with dough and brush with butter. Transfer the apple mixture to top of dough and smooth with spatula. Roll another piece of the remaining dough to 1⁄8" thickness and trim to make an 8" square; top the apple filling with dough and brush with butter. Transfer the walnut mixture to top of dough and smooth with spatula. Roll another piece of the remaining dough to 1⁄8" thickness and trim to make an 8" square; transfer the dough to top of walnut filling and brush with remaining butter. Transfer the prune mixture to top of dough and smooth with spatula; fold the overhanging dough onto the prune filling. Roll the remaining dough piece to 1⁄8" thickness and trim to make an 8" square; top the prune filling with dough, prick with a fork, and brush with the egg wash. Bake until the pastry is golden brown, 1 hour. Transfer to a rack and let cool 6 hours.
4. Using edges of parchment paper as handles, lift the pastry from pan and transfer to a cutting board. Cut flodni into 1 1⁄2" squares and serve.