makes two 9x5 inch loaves

1. In a wide saucepan, combine the milk, shortening, sugar, and salt. Place over medium heat and stir until the shortening is melted. Transfer to a large mixing bowl to cool.

2. When the mixture is barely warm to the touch, stir in the dissolved yeast. Blend in the sourdough starter. Add 2 cups of the flour and beat with a spoon until smooth. Gradually blend in additional flour until the dough becomes too difficult to stir. Turn out onto a floured surface and knead in as much of the remaining flour as necessary to form a cohesive dough. Continue kneading in flour until the dough is soft yet no longer sticks to the work surface. Transfer to a greased bowl and cover with a clean kitchen towel. Set aside to rise until double in bulk.

3. Generously grease two 9x5 inch loaf pans. Punch the dough down, then turn it out onto a floured surface. Shape it into 2 loaves and place them in the prepared pans. Cover and set aside to rise. When double in bulk, bake in a preheated 375 oven for 35 to 40 minutes, or until the crust is nicely browned. Cool on a rack for 5 minutes, then turn out. Complete cooling on the rack.