In the bowl of a stand mixer fitted with the dough hook, combine the flour, instant yeast, granulated sugar, and kosher salt.
Add the room-temperature eggs, warm milk, vanilla extract, and cooled, melted butter. Mix on low speed until a cohesive dough forms.
Increase speed to medium and knead for 8 to 10 minutes until the dough is smooth, elastic, and pulls away from the sides of the bowl.
Cover the bowl tightly with plastic wrap and let rise at room temperature for 1 to 2 hours, or until doubled in size.
Shape & Layer
Generously grease a 12-cup Bundt pan with softened butter. Punch down the dough and transfer it to a lightly floured surface. Roll into a ¼-inch-thick rectangle.
Use a pizza cutter or bench scraper to slice the dough into small, 1-inch squares. Roll each square between your palms into a smooth ball.
Melt the coating butter in one bowl and whisk the granulated sugar and cinnamon in a second bowl. Dip each dough ball into the melted butter, roll in cinnamon sugar, and layer evenly into the prepared Bundt pan.
Cover the pan loosely with a towel and rest for 20 minutes. Preheat your oven to 180°C (350°F).
Add Sauce & Bake
Whisk the melted butter and brown sugar together in a small bowl until smooth. Pour evenly over the layered dough in the pan.
Bake for 30 to 40 minutes, until the top is deep golden brown and the center is baked through.
Invert & Serve
Remove from the oven and cool in the pan for exactly 5 minutes. Place a large serving platter upside down over the bundt pan, carefully invert both, then gently tap the pan to release the bread. Serve warm.
Notes
Invert Immediately: Invert the bundt pan onto a serving platter within 5 minutes of coming out of the oven. If left longer, the brown sugar caramel glaze cools and hardens, sticking the bread to the pan.
Milk Temperature: Keep the milk warm between 100°F–110°F (38°C–43°C). Milk above 110°F will kill the yeast, resulting in dense, flat dough.
Weigh Ingredients: For accurate results, weigh flour and liquids in grams with a digital scale rather than measuring by volume.
Overnight Proofing: Assemble dough balls in the greased bundt pan without the brown sugar sauce. Cover tightly with plastic wrap and refrigerate for up to 12 hours. The next morning, let rest at room temperature for 45 to 60 minutes until puffy, pour brown sugar sauce over top, and bake.
Storage & Reheating: Store at room temperature in an airtight container for up to 3 days. Reheat single portions in the microwave for 15 to 20 seconds to soften the bread and remelt the caramel sauce.