Amy Scherber's Chocolate Rolls

• 1 egg yolk
• 230 gr warm brewed
• 210 gr unbleached all-purpose flour
• 110 ml water (cold)
• 75 gr chocolate chips
• 55 ml warm water (very)
• 22 gr unsweetened cocoa powder
• 8 gr dry yeast (active)
• 6 gr butter softened (unsalted)
• 4 gr kosher salt