Melt the unsalted butter amounts called for: melt 2 tablespoons (28 g) and separately melt 1/2 cup (113 g). Set the 2 tablespoons aside for the dough and reserve the 1/2 cup for greasing/dipping the dough balls.

In a small cup or bowl, combine 1/2 cup (120 ml) warm water, 2 1/2 teaspoons active yeast, and 1 tablespoon of the 3 tablespoons (35 g) granulated sugar. Stir gently and let sit 5–10 minutes, until the mixture is foamy.

In the bowl of a stand mixer fitted with the dough hook, add 1 cup of the 3 1/2 cups (420 g) all-purpose flour, 1 teaspoon salt, the remaining granulated sugar (2 tablespoons), 1 tablespoon light brown sugar (12 g), 1/2 teaspoon pure vanilla extract, 1 large room-temperature egg, 3/4 cup (180 ml) warm whole milk, the reserved 2 tablespoons (28 g) melted unsalted butter, and the foamed yeast mixture. Mix on low speed until combined.

With the mixer running on low, add the remaining 2 1/2 cups (approximately 300 g) all-purpose flour a little at a time until the dough comes together. Increase speed to medium-low and knead with the dough hook until the dough is smooth, elastic, and pulls away from the sides of the bowl, about 5–8 minutes.

Transfer the dough to a lightly oiled or lightly floured bowl (use a small amount of the reserved melted butter if you prefer), cover tightly with plastic wrap, and let rise in a warm draft-free place until doubled in size, about 45–60 minutes.

Meanwhile, in a medium bowl combine 1 1/2 cups (180 g) brown sugar with 1 1/2 teaspoons ground cinnamon and mix well; set aside.

Lightly grease a bundt pan with some of the reserved 1/2 cup (113 g) melted unsalted butter.

When the dough has doubled, turn it out onto a lightly floured surface and gently deflate it. Divide the dough into 32 equal pieces (or your preferred number of small balls). Roll each piece into a smooth ball.

Working one at a time, use a fork or tongs to dip each dough ball into the reserved 1/2 cup (113 g) melted butter, then immediately roll it in the brown sugar–cinnamon mixture until well coated. Place each coated ball into the prepared bundt pan, arranging them evenly.

Once all balls are coated and in the pan, cover the pan loosely with plastic wrap or a damp cloth and let the shaped dough rise in a warm place until the dough has almost doubled and the balls are puffy, about 30–40 minutes.

While the dough is finishing its second rise, preheat the oven to 350°F (180°C).

Bake the bundt pan in the preheated oven for 35 minutes, until the top is golden brown and the pieces are set.

Remove the pan from the oven and let it cool on a wire rack for 10 minutes. Run a thin knife around the edges if needed, then invert the pan onto a serving plate to release the monkey bread. Serve warm.