Knead using slamming method until dough is smooth and gluten formed. About 5 minutes.
Add the butter and salt, then continue to knead until window pane stage. Should not be more than 15 minutes. Here's where you cannot be an over achiever. If you want to get that hand-glove window pane and fail to do so in 15 minutes, but the dough passes the window pane, move on. Otherwise your dough will oxidise and you'll get the 'bubbled' over-knead bread. Not nice and won't stay soft for more than an hour.
Place the dough in an oiled bowl, spray top with water and cover to rise until double. About 1 hour.
Then shape and/or fill with whatever you desire.
Proof for another 45 minutes or until the dough becomes 2.5 times its size (if your filing is cold, you might need to increase the time). I put it into my steam oven and set it to 38C, perfect for proofing breads.
Bake at 180C for small breads for 15 minutes, and 170C for 25 minutes for loaves.
Your bread is done when 2/3 of the bottom and the 'waist' of the bread are slightly brown.