Dough:

1. In the bowl of a stand mixer, or large mixing bowl, add the milk, yeast and egg then whisk to combine. Next, add the sugar, cardamom, and salt and whisk again until combined. 
2. Turn the mixer on the lowest setting and begin slowly adding the bread flour, a ½ cup at a time, allowing the flour to become mostly incorporated before adding the next scoop. Continue until all the flour has been added, scraping down the sides as necessary. Add in all of your butter and continue mixing until fully incorporated, about 4 minutes. 
3. Increase the speed to medium, and let the mixer knead and incorporate until smooth and elastic, about 8–10 minutes. Transfer the dough to your work surface, knead into a ball, then place in a greased bowl. Cover with plastic wrap or a damp towel, and let proof at room temperature for about 45–60 minutes, or until doubled in size.

Filling:

1. In a large mixing bowl, combine the butter, dark brown sugar, salt, cinnamon, and cardamom. Beat with an electric mixer or whisk until smooth and homogeneous. Finally, add the light brown sugar and continue to mix until incorporated.

Shaping: 

1. Gently punch down your dough to degas before transferring to a lightly floured work surface. Lightly flour the top of your dough as well. Using a rolling pin, shape the dough into a 22” wide x 15” tall (56 x 38 cm) rectangle, making sure it is evenly thin across the entire surface area.
2. Leaving a ½” (1.3 cm) border around the perimeter of the dough, place dollops of the filling evenly across the surface. Using an offset spatula, spread the filling into a uniform layer.
3. Grab the left side of the dough and fold over itself ⅔ of the way to the right edge. Brush off any excess flour at this stage as it will prevent the dough from properly adhering to itself. Now, take the right side of the dough and fold up and over the first fold, with the right edge meeting the left edge. Pat gently then lightly roll from bottom to top with the rolling pin to help the layers stick together and push out any air bubbles. 
4. Rotate the dough 90°, lightly flour both sides, then roll until it reaches 24” (61 cm) wide x 8” (20 cm) tall. Next, mark 1” (2.5 cm) intervals across the entire width of the dough so you can divide evenly into 24 strips. Using a pizza cutter, or knife, cut as straight as possible along the notches.
5. Gently grab one of the strips by the ends then carefully stretch the dough, slapping it on your work surface as necessary, until it is roughly 18” (46 cm). Once the filling begins to spill out, stop stretching. Twist the dough 3-4 times until it forms a loose braid. Grab one end of the braid between your thumb and first two fingers then twist it twice around these fingers. With your other hand, take the loose end and pull it up and over the gap where the tips of your fingers are holding the dough. Remove the fingers that were originally holding the dough, being careful not to mess up the structure you have created. Finally, stuff the loose end around the bottom edge into the hole where your fingers once were. Press gently to adhere everything together.

Proof and Bake:

1. Using a pastry brush, spread a thin layer of softened butter in each hole of two regular sized 12-muffin tins *see Notes*. Sprinkle a tiny amount (~½ tsp) of light brown sugar in the bottom of the holes, shaking out any excess. Transfer the shaped buns to the prepared pan, then cover with greased plastic wrap. Let proof at room temperature until for about 1.5x in size, about 45-60 minutes. 
2. In a small mixing bowl, whisk together the egg and milk until thoroughly combined and homogeneous. Use a pastry brush to brush each bun lightly and evenly with the egg wash.
3. Bake at 375°F (190°C) for 18-20 minutes, or until golden brown on top and the bottoms have caramelized. Remove from the oven and let cool in the pan for 2-3 minutes before transferring them to a wire rack set over a baking sheet. Let cool for an additional 5-10 minutes. Serve and enjoy!

*Notes:

• Alternatively, you can place the buns directly on a lightly greased baking sheet and bake them the same way. You’ll have to skip the brown sugar sprinkle on the bottom of the buns with this method.