In a small bowl, stir together 1/3 cup (80g) warm water, warm milk, yeast, and 1 teaspoon (4g) sugar. Let stand until foamy, 5 to 10 minutes.
In the bowl of a stand mixer, whisk together 2 3/4 cups (344g) flour, salt, and remaining 3 tablespoons plus 2 teaspoons (46g) sugar. Add yeast mixture and 2 eggs (100g); using the paddle attachment, beat at low speed until a shaggy dough forms. Scrape sides of bowl.
Switch to the dough hook attachment. Beat at low speed until dough is smooth and elastic, about 6 minutes; add up to 1/4 cup (32g) flour, 1 tablespoon (8g) at a time, if dough is too sticky. Add butter, 1 tablespoon (14g) at a time, beating until combined after each addition (about 5 minutes total). Beat until a smooth, slightly tacky, and elastic dough forms, 9 to 10 minutes; add up to remaining 1/4 cup (32g) flour, 1 tablespoon (8g) at a time, if dough is too sticky.
In a small bowl, stir together chocolate, cherries, and pistachios. Add to dough, and beat at low speed until just combined, stopping to scrape sides of bowl and dough hook. Turn out onto a lightly floured surface, and knead 3 to 5 times to ensure mix-ins are evenly distributed. Shape dough into a smooth round.
Lightly oil a large bowl. Place dough in bowl, turning to grease top. Cover and let rise in a warm, draft-free place (75°F/24°C) until doubled in size, 45 minutes to 1 hour.
Punch down dough, and let stand for 10 to 15 minutes. On a lightly floured surface, divide dough into 7 portions (about 127 grams each). Press each portion into a disk about ¾-inch thick. Working clockwise around each disk, fold edges toward center to form a ball. Turn dough seam side down. Cover and let stand for 15 to 20 minutes.
Line a baking sheet with parchment paper.
On a lightly floured surface, place 1 dough ball seam side up, and press into a 3¼-inch-wide disk. Starting with top edge, fold dough, about 1/2 inch at a time, pressing to seal after each fold. Repeat until you have a tight cylinder. Roll seal to bottom, and using both hands, gently roll from center out toward ends, lengthening dough as you go and tapering ends. Dough should be 7 inches long. Repeat with remaining dough. Place, seam side down, about 2 inches apart on prepared pan. Cover and let rise in a warm, draft-free place (75°F/24°C) until doubled in size, 45 minutes to 1 hour.
Preheat oven to 375°F (190°C).
In a small bowl, lightly whisk remaining 1 egg (50g). Brush tops and sides of each roll with egg wash. Using a lame or a sharp paring knife, score tops with small diagonal cuts, about ½ inch apart.
Bake until an instant-read thermometer inserted in center registers 190°F (88°C), 10 to 12 minutes. Let cool on pan for 10 minutes. Serve warm, or remove from pan, and let cool completely on a wire rack.