Measure sourdough starter into large bowl and mix in yeast, milk, and butter with warm water.
Add all-purpose flour while mixing.
Knead to form dough that is soft and elastic. (I use an electric mixer for 6-8 minutes)
Place the dough in a lightly greased bowl.
Cover for dough to allow bulk fermentation for 9hrs ( I start after dinner and let it sit overnight.
Once dough doubles, turn it out on a floured work area and let this sit for 30 minutes to relax the gluten.
Cut dough into 330gr sample; this recipe will yield 3 loaves'.
Spread out 1 dough ball into a rectangle shape rolling the dough on top of itself to form loaf.
Follow this process for each dough ball.
Place loaves' into nonstick baguette pan covering with butter sprayed parchment paper.
Cover with teacloth and let rise for 4 hours.
Preheat oven to 475F
placing a shallow pan of hot water on the rack below the rack you will place the baguettes.
Be aware of your oven and place the baguettes no higher than the center of the oven.
Spray baguettes with salt water solution and score the loaf tops 4 times to allow steam to escape.
Bake baguettes for 13 minutes at 475F; then turn the oven down t 450F.
Continue baking for another 13 - 15 minutes.
Remove from the oven and brush lightly with butter.