Cinnamon Bubble Buns

Yogurt yeast dough:
2¼ teaspoons dried yeast
¼ cup (60 ml) warm water
3 tablespoons (42g) unsalted butter, melted and cooled
2/3 cup plain yogurt
3 tablespoons granulated sugar
1 large egg
1 teaspoon pure vanilla extract
320g all-purpose flour + a little for kneading, if necessary
¼ teaspoon salt
¼ teaspoon baking soda

Cinnamon-sugar coating:
65g light brown sugar
1 teaspoon ground cinnamon
2 tablespoons unsalted butter, melted

Dough: sprinkle the yeast over the water in the bowl of a stand mixer; set aside for 5 to 10 minutes until bubbly. Add the butter, yogurt, sugar, egg, and vanilla to the yeast mixture and stir to combine with a rubber spatula.
Attach the bowl to the mixer, and fit the mixer with the paddle attachment. Beat in 250g of the flour, the salt, and baking soda on medium-low speed until incorporated, 30 to 45 seconds. Add the remaining 70g flour and beat until a smooth, moderately soft dough forms.
Turn the dough out onto a lightly floured work surface and knead until smooth and satiny, about 3 minutes. At first the dough will be sticky. Add no more than 1 to 2 tablespoons additional flour during the kneading to combat the stickiness. Place the dough back in the bowl, cover tightly with plastic wrap, and let rise in a warm place until doubled in size, about 1 hour. The dough is ready when a finger gently pressed into it leaves an indentation. Meanwhile, prepare the pan and make the cinnamon-sugar coating.

Generously butter a 12-cup standard muffin pan (1/3 cup capacity each cavity), then flour the cups, tapping out the excess flour. 
Cinnamon-sugar coating: in a small bowl, stir together the sugar and cinnamon; set nearby. Place the melted butter in a small, shallow dish.
Gently punch the dough down to deflate it. Form it into a long cylinder, and divide it into 12 equal portions (each portion is about 1¾ ounces/50 grams). Divide each portion into 6 equal pieces, and then shape each piece into a ball. One at a time, roll the balls first in the butter and then in the cinnamon sugar. Arrange 5 balls next to one another in a circle in each prepared muffin cup, and then, using a fingertip, poke the sixth ball down slightly in the center.

Repeat with the remaining 11 dough portions. Loosely cover the buns with plastic wrap and set them aside in a warm place until puffy and doubled in volume, about 40 minutes. The dough is ready to bake when a finger gently pressed into it leaves an indentation – in the meantime, center a rack in the oven and preheat the oven to 180°C/350°F.
Bake the buns until golden, 20-22 minutes. Transfer the pan to a wire rack and let cool for 5 to 8 minutes. Then tilt the pan and gently tap it on a counter to release the buns. If necessary, slip a knife blade between the pan and the bun to release. Transfer the buns to a wire rack.

Makes 12