Mix the Dough:

1. In the bowl of a stand mixer whisk together the dry active yeast and warm milk. Allow to sit for 10 minutes or until bubbly.
2. Add the sugar, eggs, salt, and flour to the stand mixer bowl. Fit with the paddle attachment and mix to incorporate.
3. Once the ingredients are mixed and the flour has been hydrated, switch to the hook attachment and mix on medium until a smooth dough forms. Use the window pane test to tell if the dough is ready to add the butter.
   WINDOW PANE TEST: take a golf ball sized portion of the dough from the mixer and gently start to pull the dough apart. I like to think of it as a square and gently pull on two sides, then rotate and repeat. If the dough tears instantly, it is definitely not ready. If it allows you to pull it thin enough to see light through it, then it is ready. There are different degrees of gluten development but with this dough we want to develop a strong gluten network to hold up to all that butter and eggs! Ideally you want a smooth dough with no visible “veins”.
4. Add the softened butter to the stand mixer and mix on low until the butter disappears into the dough.
5. Adding the butter after developing the gluten shortens the mixing process and will ensure a nice strong dough that will support all those eggs and that butter! You can add the butter with all the rest of the ingredients in Step 2, but it will take longer to develop. You might need to stop mixing before the perfect window pane has been achieved. If that is the case, simply add another set of folds to develop the gluten instead.

Shaping & Proofing

1. Remove the dough from the stand mixer using a stiff silicone spatula or a bowl scraper, and place it in a lightly oiled bowl. Cover with plastic wrap and then place in a warm spot. Allow to proof 30 minutes. Give the dough one set of folds.
2. Set of folds: A set of folds is actually 4 separate folds. Fold each of the four sides into the center by pulling the dough up on one side and then fold it over on top of the remaining dough in the bowl. Rotate the bowl after each fold. This is developing more gluten!
3. Bulk Proof: Cover the dough and place back into the warm spot to proof. Check the dough every 45 minutes. This will take about 1 ½ hours. You want to oil or flour your hand and feel the dough. It should feel light and airy and not stiff or dense.
4. Pre-shape & Bench rest: Turn the dough out onto a lightly or un-floured surface. Fold each of the four sides towards you into the center, turning the dough after each fold. This will create a little packet. Flip the dough so the seam in on the counter. Shape it into a round by using both hands to pull the dough towards you. Once you have a round ball with a smooth top, cover to keep the top from drying out and allow it to sit and bench rest for 15 minutes.
5. Final Shape: We are going to shape these into a log (or a bâtard if you like fancy French terms for things). Take the dough round and flip it over. Grab the top and bottom edges and gently pull it into a small rectangle. Place it on the counter and fold the top edge down 2/3^rd of the way and press it into the dough. Rotate so that the unfolded edge is now away from you and fold that edge down towards you to meet the bottom edge. Press to seal. Now we are going to do 2 thumb folds. Take the top edge with your right hand and fold it over you thumb about half way down, pressing to seal as you go. Repeat until you have folded the entire length. You will notice the dough getting tighter and also longer.
6. Repeat the thumb fold once more, sealing really well on the bottom. You should now have a log shape that is even in width along the whole length, that is the length of your pan, and tight enough to not slouch onto the counter. If the dough is too loose, repeat the thumb fold once more.
7. Spray with non-stick spray or butter a 9×5 inch loaf pan. Place the log into the sprayed pan seam-side down. Cover with plastic wrap and place once more in your warm spot.
8. Allow to proof until the dough just starts to reach the top of the pan. When that happens preheat  your oven to 350°F. As soon as it is preheated bake for 35-40 minutes or until the internal temperature reads 185°F.
9. Allow to cool 5 minutes in the pan then remove to a rack to cool completely.