I would use sponge and dough method. 60%. Or you could use pate fermentee and add the enrichments into the dough. What's white pan bread? 100% flour, 60% h2o plus or minus, 2.5-3% salt, 3% yeast (fresh) 5% sugar, 2.5% dried milk powder, 5% butter or shortening...something like that. Make the sponge with 60% of the water, flour, and yeast and all of the sugar, milk, butter. ferment for three hours or so, and then make the dough with the remaining flour, water, yeast and salt. It only needs to sit for 25 minutes now, and then straight to dividing, rounding, resting and shaping. I think it makes for a more supple dough, well-hydrated.