Whisk the warm milk, yeast, and sugar together in the bowl of a stand mixer fitted with a dough hook attachment. Cover and allow the mixture to sit for about 5 minutes until foamy.

Add salt, butter, and 2 cups (250g) of flour. Beat on medium speed for 2 minutes, scraping down the bowl as needed. Add remaining flour until a soft dough forms.

Knead the dough on medium speed for 5 minutes or by hand on a floured surface until it feels slightly tacky and passes the windowpane test.

Grease a large bowl with oil, place the dough in it, cover, and allow it to rise for 1.5–2 hours until nearly double in size.

Punch down the dough and flatten it into a 10x14-inch rectangle on a lined baking sheet. Cover and refrigerate for 20 minutes.

Prepare for lamination by cutting 3/4 cup of salted butter into 1/4-inch thick slices.

For the first lamination, place butter down the center of the dough, fold edges over it, and then roll out to a 9x12-inch rectangle. Cover and refrigerate for 20 minutes.

For the second and third laminations, repeat the process: roll out to 9x12 inches, fold, and refrigerate for 20 minutes each time.

For the final lamination and shaping, roll out to 9x12 inches, fold edges over, and roll up from the 9-inch side into a log. Cut into 5 even rolls.

Grease a 9x5-inch loaf pan, place rolls seam side down in the pan, cover, and allow to rise for 45–60 minutes until slightly puffy.

Preheat the oven to 350°F (177°C).

Whisk egg wash ingredients together and brush generously over the risen rolls. Bake for 1 hour until golden brown and an instant-read thermometer reads 195°F (90°C).

Cool in the loaf pan for 30 minutes, then remove from the pan and cool for at least 15 minutes on a wire rack before slicing.