Using an electric blender, blend the pineapple for about 10 seconds, or until smooth while still retaining a slight texture. Transfer the pineapple to a non-stick pot.
Add the sugar, cloves, and cinnamon stick to a pot and cook the pineapple over medium to low heat for a few hours, stirring continuously, until the liquid evaporates and a golden jam forms. (Using a non-stick pot will prevent burning.) Turn off the heat, spread the jam, and let it cool. You can prepare the jam a day in advance and store it in the fridge.
Sift the flour, sugar, milk powder, and cornstarch twice. Using a stand mixer (or a hand mixer), cream the butter and sugar until well combined, light, and fluffy. Add the egg yolks one at a time, continuing to beat well after each addition. Gradually add the flour mixture and beat on low speed using the paddle attachment until everything is well combined.
Work with 50g (about 1¾ oz.) of pastry dough at a time. Roll the dough between two sheets of plastic to form a thin layer (refer to Indochine Kitchen for a step-by-step picture guide). Pipe the pineapple jam on top of the dough, then roll the dough to completely encase the jam.
Use a pair of scissors to cut the dough into 4 cm (1.5 inch) long rolls. Arrange the pineapple rolls on a baking sheet lined with parchment paper.
At this point, preheat the oven to 150°C (300°F). Combine the egg wash ingredients until well mixed. Brush the tops of the pineapple rolls with the egg wash mixture twice using a small pastry brush. Bake in the preheated oven until golden, about 15-20 minutes. Let the rolls cool, then store them in airtight containers.