Heat milk to luke warm, about 100 degrees. Remove from heat, pour into a bowl and whisk in yeast. Set aside while preparing other ingredients. Place flour, sugar and salt in bowl of food processor fitted with metal blade; pulse to mix. Add the 4 tablespoons butter and pulse until butter is absorbed and mixture is powdery in appearance. Add eggs and milk mixture and continue to pulse until dough forms a ball. If the dough refuses to form a ball, add up to 3 tablespoons more flour, one tablespoon at a time, pulsing once or twice between each addition.
To mix by hand, combine flour salt and sugar in a bowl and stir well to mix. Rub in butter by hand, being sure to leave mixture cool and powdery. Beat eggs until liquid and add to flour mixture along with yeast-milk mixture. Stir vigorously with a rubber spatula to form a dough.
Cover bowl with plastic wrap and allow to rest 5 minutes. Scrape dough to floured surface and fold dough over on itself 6 or 8 times, sprinkling with up to 3 tablespoons more flour if dough is very soft. Wrap dough in plastic wrap and refrigerate 1 to 8 hours.
After the dough has chilled, prepare butter: Place half the flour on work surface and place butter on it. Scatter remaining flour on butter and pound the butter with a rolling pin to soften it to a malleable consistency. Scrape butter together and form into a cylinder. Immediately remove dough from refrigerator and press in into a 6 by 12-inch rectangle on a lightly floured surface. Distribute dabs of butter in a 6 by 9-inch rectangle at the closer end of the dough, covering dough as completely as possible. Fold the top (unbuttered) portion of dough down over the middle section and the bottom (buttered) portion up to cover it. Position the dough so the fold is on the left and roll the dough back to its original size, flouring the surface and dough as necessary. Fold both short ends in to the middle of the dough and fold again at the middle, making 4 layers. Reposition the dough so that the fold is on the left again and repeat rolling and folding. Double-wrap dough in plastic wrap and refrigerate dough several hours or overnight before using.