Step 1

Cut 5 tablespoons unsalted butter into 5 pieces. Let sit out at room temperature until softened. If you plan to make the butter block the same day, let 1 pound unsalted butter sit out at room temperature until softened.

Step 2

Place 4 3/4 cups bread flour, 1/2 cup granulated sugar, 2 (1/4-ounce) packets active dry yeast, and 1 1/2 teaspoons kosher salt in the bowl of a stand mixer fitted with the dough hook and whisk to combine. Turn the mixer on to low speed. Add the softened butter 1 tablespoon at a time, waiting until each is well distributed into the flour mixture before adding the next, about 2 minutes total.

Step 3

Heat 1 2/3 cups whole milk in the microwave until 85ºF, 30 to 45 seconds. (Alternatively, heat on the stovetop.) Add the warm milk to the flour and butter mixture and mix on low speed for 3 minutes. Scrape down the sides of the bowl. Mix on medium-high speed for 3 minutes more. The dough will be sticky and slightly elastic.

Step 4

Lightly coat a large bowl with cooking spray. Transfer the dough into the bowl, then flip the dough so it's coated all over with cooking spray. Cover the bowl with plastic wrap and refrigerate for 10 to 12 hours. For fresh cruffins the next day, I suggest preparing the dough the night before you plan to bake the cruffins so that it can proof overnight in the refrigerator. Make the butter block either the night before or the morning you plan to bake the cruffins.

Step 5

Place 1 pound unsalted butter in the clean and dried bowl of a stand mixer fitted with the paddle attachment and let sit at room temperature until softened. Add 2/3 cup bread flour and beat on medium-low speed until well combined, about 1 minute.

Step 6

Place a large sheet of parchment paper on a work surface. Scrape the butter mixture onto one half of the parchment paper and spread into a 6x9-inch that's about 1/2-inch thick. Fold the other half of the parchment over the butter rectangle and wrap tightly. Refrigerate until ready to assemble.

Step 7

Let the butter block sit at room temperature about 20 minutes before rolling out the dough so that it is pliable but not not too soft to roll out.

Step 8

Lighly dust a work surface with flour. Transfer the dough onto the flour and roll out into a 10x12-inch rectangle with a long side closer to you. Unwrap the butter block and place on one half of the dough, lining up the 10-inch side of the dough with the 9-inch side of the butter block, leaving a 1/2-inch border at the top and bottom. Carefully fold the other half of dough over the butter block and pinch the excess dough around the butter block to completely seal and encase it in the dough.

Step 9

Do the first fold: Lightly dust the work surface and a rolling pin with flour. Roll out the butter-filled dough into a 13x18-inch rectangle with a shorter side closer to you. Fold the dough into thirds like a letter: Fold the top 1/3 down, then fold the bottom 1/3 up. Wrap the dough with plastic wrap and refrigerate for 30 minutes.

Step 10

Do the second fold: Repeat rolling out the dough into a 13x18-inch rectangle and fold into thirds again. Re-wrap in the plastic wrap and refrigerate for 30 minutes.

Step 11

Do three more folds: Repeat rolling, folding, and refrigerating three more times, for a total of 5 folds. After the fifth and final fold, while the dough is chilling for the last 30 minutes, generously coat 2 standard (12-well) muffin pans with butter. Place 1 3/4 cups granulated sugar and 2 tablespoons ground cinnamon in a small bowl and stir to combine. Beat 1 large egg in a second small bowl.

Step 12

Divide the dough in half and re-wrap and refrigerate one half. Place the other half on a lightly dusted work surface and roll out into a 12x20-inch rectangle with a shorter side closer to you. Lightly brush the dough with the beaten egg. Sprinkle with half of the cinnamon sugar mixture, going all the way to the edges. Using a knife or pizza cutter, cut the dough vertically into 12 (1-inch wide) strips.

Step 13

Starting at the bottom end, roll up each strip into a tight coil. Place a coil seam-side down in each muffin well. To make sure the cruffins grow into a nice cone shape, but not too high out of the muffin tin, make sure the coil is flat and hasn’t come to a “point” in the center when you roll it and place it in the muffin tin; if you have a point, press down lightly on it to flatten.

Step 14

Repeat rolling out and assembling the remaining cruffins. Cover the muffin tins with lightly greased plastic wrap and let rise in a warm place until the cruffins begin to puff and fill the wells, about 45 minutes. About 20 minutes before they are ready, arrange 2 racks to divide the oven into thirds and heat the oven to 375°F.

Step 15

Uncover and bake for 15 minutes. Rotate the muffin tins from top to bottom and front to back. Bake until golden-brown, 12 to 17 minutes more. Let cool for a few minutes in the tins before transferring to wire racks. Let cool for at least 10 minutes before serving.