1 3/4 teaspoons active dry yeast (from one 1/4-ounce envelope)
2 large eggs, room temperature
2 3/4 cups unbleached all-purpose flour
1 teaspoon kosher salt
1/2 cup (1 stick) unsalted butter, cut into 1-inch pieces, room temperature, plus 1/2 tablespoon, melted
1 3/4 cups chopped pecans (about 8 ounces)
1/2 cup (1 stick) unsalted butter
3/4 cup (packed) dark brown sugar
3/4 cup heavy cream
1/3 cup honey
1/4 teaspoon kosher salt
1/4 teaspoon finely grated orange zest (optional)
1/2 cup (1 stick) unsalted butter, room temperature
1/2 cup (packed) dark brown sugar
3/4 teaspoon ground cinnamon
1/2 teaspoon freshly grated nutmeg
1/8 teaspoon kosher salt
All-purpose flour (for dusting)
1 large egg
Coarse sea salt (such as Maldon)
Heat milk in a small saucepan over medium heat or in a microwave until an instant-read thermometer registers 110°–115°. Transfer milk to a 2-cup measuring cup; stir in 1 Tbsp. sugar. Sprinkle yeast over milk and whisk to blend. Let sit until yeast is foamy, about 5 minutes. Add eggs; whisk until smooth. Combine remaining 4 Tbsp. sugar, flour, and salt in the bowl of a stand mixer fitted with a dough hook. Add milk mixture. With mixer running, add 1/2 cup room-temperature butter, 1 piece at a time, blending well between additions. Mix on medium speed for 1 minute. Knead on medium-high speed until dough is soft and silky, about 5 minutes.
If you don't have a stand mixer, fit your food processor with the standard chopping or dough blade. Combine remaining 4 Tbsp. sugar, flour, and salt in food processor. Pulse to blend. Add milk mixture; process until combined. With processor running, add 1/2 cup room-temperature butter, 1 piece at a time, blending well between additions. Process until dough is soft and silky, 2–3 minutes longer. Dough will be sticky but should not be greasy. If it is greasy, process for an additional 1–2 minutes.
Brush a medium bowl with some melted butter; place dough in bowl. Brush top of dough with remaining melted butter; cover with plastic wrap. DO AHEAD: Can be made 1 day ahead. Cover with plastic; chill.
Let dough rise in a warm, draft-free area until doubled in size, 1–1 1/2 hours (or 2–2 1/2 hours if dough has been refrigerated).
Chill dough for 2 hours.
Preheat oven to 350°. Spread out nuts on a rimmed baking sheet. Toast until fragrant and slightly darkened, 10–12 minutes. Let cool completely. Set 1 1/4 cups nuts aside for buns.
Melt butter in a small heavy saucepan over medium heat. Stir in brown sugar, cream, honey, salt, and orange zest, if using. Bring to a boil, reduce heat to medium, and simmer until glaze is golden brown and glossy, 3–4 minutes. Pour 1 cup of glaze into baking pan, tilting to coat bottom and sides. Set aside remaining glaze. Sprinkle 1/2 cup toasted pecans over bottom of baking pan and let cool.
Using an electric mixer on medium speed, beat butter, sugar, cinnamon, nutmeg, and kosher salt in a medium bowl until light and fluffy, 2–3 minutes. Set filling aside.
Punch down dough; transfer to a floured work surface. Lightly dust top with flour. Follow our step-by-step guide for assembling buns with filling and 3/4 cup pecans. DO AHEAD: Can be made 1 day ahead. Cover and chill buns and remaining glaze separately. Store remaining pecans airtight at room temperature.
Loosely cover pan with plastic wrap or a kitchen towel. Let buns rise in a warm, draft-free area until doubled in size, 45 minutes to 1 hour, or 1 1/2–2 hours if dough has been chilled overnight.
Arrange a rack in middle of oven; preheat to 350°. Whisk egg with 1/2 tsp. water in a small bowl. Brush tops of buns with egg wash. Bake, rotating pan halfway through and tenting with foil if browning too quickly, until buns are golden brown, filling is bubbling, and an instant-read thermometer inserted into center of buns registers 185°, about 50 minutes. Let cool for 5 minutes. Spoon remaining glaze over. Sprinkle 1/2 cup pecans over. Let cool in pan on a wire rack.
Lightly sprinkle sea salt over. Serve buns warm or at room temperature.