Place the flour, sugar, yeast, and salt in a large bowl and whisk together until combined. Slice the butter into ⅛-inch thick slices and toss in the flour mixture to coat.
Add the milk and stir together until a stiff, shaggy dough forms. (The dough may seem a little dry, but it will hydrate as it chills.)
Wrap the dough tightly in plastic wrap and chill for 1 hour. On a lightly floured surface, roll the dough into a long rectangle shape.
Fold it into thirds (like a letter), turn 90 degrees, and repeat 3 to 5 more times (or until the dough has large streaks of butter in it but it is smooth and flat). (If at any point the butter starts to feel soft, chill the pastry in the refrigerator or freezer until stiff.)
Wrap and chill the laminated dough for another hour.
On a lightly floured work surface, roll the dough into a rectangle shape about ⅛-inch thick.
Sprinkle on an even layer of the filling mixture.
Roll into a long log, then flatten the log.
Divide each half into 3 portions, then split each portion lengthwise.
Roll each portion into a spiral, then place in the wells of a muffin tin, cut side up.
Cover lightly with plastic wrap and allow the pastries to rise for 1 hour, or refrigerate overnight. Preheat the oven to 375 degrees F.
Bake until puffed and golden brown (approx. 20 to 30 minutes).