Ingredients

Bun Dough

• ¼ cup bread flour
• ⅔ cup water
• ⅔ cup milk
• 1 large egg plus 1 yolk
• 2¾ cups bread flour
• 2 teaspoons instant or rapid-rise yeast
• 3 tablespoons granulated sugar
• 1½ teaspoons salt
• 6 tablespoons unsalted butter, softened

Sweet Topping

• ½ cup packed dark brown sugar
• 6 tablespoons unsalted butter, melted
• ¼ cup granulated sugar
• ¼ cup dark corn syrup
• ¼ teaspoon salt
• 2 tablespoons water
• 1 cup pecans, toasted and chopped

Filling

• 1 teaspoon cinnamon
• ¾ cup packed dark brown sugar

Directions

1. Whisk first two ingredients (flour and water) together in small bowl until smooth. Microwave, whisking every 25 seconds, until mixture thickens to stiff, smooth, pudding-like consistency that forms mound when dropped from end of whisk into bowl. Do this 2 to 3 times for a total of 50 to 75 seconds.
2. In a mixing bowl, whisk flour paste with milk until smooth. Add egg and yolk and whisk until incorporated. Add flour and yeast. Fit mixer with dough hook and mix on low speed until all flour is moistened, 1 to 2 minutes. Let stand for 15 minutes. Add sugar and salt and mix on medium-low speed for 5 minutes. Stop mixer and add butter. Continue to mix on medium-low speed for 5 minutes longer, scraping down dough hook and sides of bowl halfway through (dough will stick to bottom of bowl).
3. Transfer dough to lightly floured counter. Knead briefly to form ball and transfer seam side down to lightly greased bowl; lightly coat surface of dough with vegetable oil spray and cover bowl with plastic wrap. Let dough rise until just doubled in volume, 40 minutes to 1 hour.
4. While dough rises, grease 13×9-inch metal baking pan. Whisk melted butter, brown sugar, granulated sugar, corn syrup, and salt together in medium bowl until smooth. Add water and whisk until incorporated. Pour mixture into prepared pan and spread evenly to cover bottom. Sprinkle evenly with pecans.
5. Combine brown sugar and cinnamon in small bowl and mix until thoroughly combined; set aside.
6. Turn out dough onto lightly floured counter. Press dough gently but firmly to expel air. Working from center toward edge, pat and stretch dough to form 18 by 15-inch rectangle with long edge nearest you. Sprinkle cinnamon sugar over dough, leaving 1-inch border along top edge; smooth filling into even layer with your hand, then gently press mixture into dough to adhere.
7. Roll dough along using the longer side into cylinder, taking care not to roll too tightly. Pinch seam to seal and roll cylinder seam side down. Mark gently with knife to create 12 equal portions. To slice, use dental floss.  Slide one end underneath and the other, over the top.  Cross ends of floss over each other and pull. Slice cylinder into 12 portions.  Transfer each piece cut sides down, to prepared baking pan. Cover tightly with plastic wrap and let rise until buns are puffy and touching one another, 40 minutes to 1 hour. (At this point, may be refrigerated for up to 14 hours.) To bake, remove baking pan from refrigerator and let sit until buns are puffy and touching one another, 1 to 1 1/2 hours.)
8. Pre heat over to 375 °F.  Adjust oven racks to lowest and lower-middle positions. Place rimmed baking sheet on lower rack to catch any drips.
9. Bake buns on upper rack until golden brown, about 20 minutes. Tent with aluminum foil and bake another, 10 to 15 minutes longer. Let buns cool in pan on wire rack for 5 minutes. Place rimmed baking sheet over buns and carefully invert. Remove pan and let buns cool for 5 minutes. Using spoon, scoop any glaze on baking sheet onto buns. Let cool for at least 10 minutes longer before serving.