Combine 1/2 tsp yeast and warm milk. Let stand 5 minutes. Add milk mixture, sponge, room temperature water, olive oil and flour to a stand mixer fitted with a dough hook. Stir until flour is moistened. Turn speed to 3 and let mix 2 minutes. Add salt and mix on speed 3 1 more minute.
Preheat oven to 425. (If you have a baking stone, add it to the oven at this stage.) Line a baking sheet with parchment paper.
Add dough to oiled bowl and cover loosely with plastic wrap. Place in a warm, draft free place for 45 minutes.
Divide dough into fourths. Form flattish round with each portion of dough. Place on baking sheet and flatten with palm of hand.
Bake at 425 for 12-15 minutes or until rolls are light brown and sound hollow when tapped. Let cool before slicing.