With the mixer still on low, add the remaining ½ cup of flour and continue mixing for a couple more minutes. If needed switch from the paddle attachment to the dough hook.
With the mixer on low speed, add 2 cups of the flour and mix for 5 minutes. Add the 2 more cups of flour and mix for 5 more minutes. With the mixer still on low speed add the chunks of soft butter and mix until the butter is fully incorporated in the dough.
Add the eggs, and with the mixer on medium, beat for about a minute after which add the 2 teaspoons of salt.
Start by preparing the yeast with warm water and sugar in the mixer bowl, stir them all together and let the yeast do its magic for about 5 minutes. You'll notice it will get bubbly.