Mix water, yeast and sugar in a small bowl. Cover and let proof 5 minutes.
In a mixing bowl combine yeast mixture, oil and salt.
Stir in flour, one cup at a time until soft dough forms.
Knead dough on a lightly floured surface until elastic, about 5 minutes. Cover and let rest 25 minutes.
Cook sausage, drain.
Roll dough out to a 9"x18" rectangle. Spread with butter.
Sprinkle with sausage, cheese and red pepper flakes (to taste).
Roll bread into a long loaf shape. Pinch seams and ends to close.
Place loaf on a greased baking sheet. Cover and let rest 25 minutes.
Bake at 400 degrees for 25-30 minutes or until golden brown.
Cool 20 minutes before slicing.