In the bowl of a stand mixer, add the yeast, sugar, and warm milk. Stir together and let sit for 5 minutes until the yeast is foamy.
Add the paddle attachment to the mixer, then pour in the salt, melted butter and 2½ cups flour. Run the mixer on low until the dough comes together (it will be shaggy), adding up to ¼ cup more flour if needed.
Turn the dough out onto a floured surface, form into a ½" thick rectangle, wrap in plastic wrap and refrigerate for 45 minutes.
While the dough is chilling, cut the sticks of butter in half lengthwise. Remove the dough from the fridge onto a lightly floured surface and roll out to a 9 x 13" rectangle.
Turn the dough so that the 9" side is towards you. Place the sticks of butter vertically and side-by-side (touching) on the center of the dough. Fold the bottom ⅓ up over the butter, then fold the top ⅓ down (think folding a letter). Press the outside edges together to seal the butter in.
Rotate the dough 90 degrees; folded side should be to your left. Dust with additional flour, if necessary, and roll the dough out to a 10 x 20" rectangle. Repeat the letter folds- bottom ⅓ folded up, top ⅓ folded down. Wrap in plastic wrap and refrigerate for 45 minutes.
Repeat Step 7 an additional three times. Allow dough to chill for 90 minutes, or up to overnight, after the last time.
Line two baking trays with parchment paper or silicone mats. Roll out the dough on a floured surface to a size of 9x18". Cut dough in half lengthwise, then cut each of those into 4 squares/rectangles. You should have 8. Cut each square diagonally to make rectangles.
Working with one triangle at a time, roll up the dough from the wide end to the pointed end, gently slightly stretching the dough as you go. Place the rolled dough, tip down, on the baking sheet. Gently curve into a crescent shape, if desired. Repeat with remaining triangles.
Let rolls rise for approximately an hour and a half. Preheat oven to 400F and position racks in the upper and lower thirds of the oven.
Brush the rolls with the egg wash and place in preheated oven for 10-15 minutes, until desired level of golden is achieved, rotating the trays halfway through. Remove from the oven and allow to cool slightly before serving.