In the bowl of a stand mixer, whisk together 1/3 cup (80 grams) warm milk, 1 tablespoon (12 grams) granulated sugar, and yeast. Let stand until foamy, about 10 minutes.
Add 1 cup (125 grams) flour and room temperature eggs to yeast mixture; using the paddle attachment, beat at medium low speed until a shaggy mixture forms, 2 to 3 minutes, stopping to scrape sides of bowl.
Switch to the dough hook attachment. Add 1 cup (125 grams) flour, salt, and remaining 3 tablespoons (36 grams) granulated sugar; beat at low speed just until combined. Increase mixer speed to medium, and beat until dough is smooth and elastic, 7 to 10 minutes, stopping to scrape sides of bowl; add up to remaining ¼ cup (31 grams) flour, 1 tablespoon (8 grams) at a time, if dough is too sticky.
Add butter, 1 tablespoon (14 grams) at a time, to dough, beating until combined after each addition. Beat until dough pulls away from bottom and sides of bowl, becomes smooth and elastic, and passes the windowpane test, 6 to 8 minutes.
Spray a large bowl with cooking spray. Place dough in bowl, turning to grease top. Cover and let rise in a warm, draftfree place (75°F/24°C) until doubled in size, 45 minutes to 1 hour.
Punch down dough, and turn out onto a lightly floured surface. Flatten into a 10x6-inch rectangle, and transfer to a parchment paper-lined baking sheet. Cover and refrigerate for at least 5 hours or up to overnight.
In a medium bowl, combine raisins and warm brandy; let stand for 20 minutes.
Line a baking sheet with parchment paper.
Turn out dough onto a heavily floured surface; lightly dust top of dough with flour. Roll dough into a 14x11-inch rectangle. Using a small offset spatula, dot Pastry Cream onto dough; spread into an even layer, leaving a ½-inch border on one long side.
Drain raisins, and sprinkle onto Pastry Cream. Starting with long side opposite border, roll up dough into a 14-inch-long log. Gently stretch and shape log with hands to lengthen and even out thickness, if necessary. Using a serrated knife or unflavored dental floss, trim ends of log if necessary, and cut log into 12 slices (about 11/8 inches thick each). Place slices, cut side down, on prepared pan. Loosely cover and let rise in a warm, draft-free place (75°F/24°C) until puffed, 30 to 45 minutes.
Preheat oven to 375°F (190°C).
In a small bowl, whisk together egg and 1 tablespoon (15 grams) water; brush onto slices. Sprinkle with pearl sugar.
Bake until golden brown and an instant-read thermometer inserted in center registers 190°F (88°C), 12 to 15 minutes. Let cool on pan for 10 minutes. Remove from pan, and let cool on a wire rack for 5 minutes. Best served warm. Store in an airtight container for up to 2 days.