Stir 2 cups flour, salt, and 1/2 cup water into yeast mixture. Knead 2 to 3 minutes with hands or dough hook of electric mixer until dough is smooth. Add remaining 1/2 cup flour and olive oil; knead 2 to 3 minutes more, or until dough comes together. Transfer to floured work surface, and knead 5 to 7 minutes more, or until dough is no longer sticky. Shape into ball, place in floured bowl, and cover with kitchen towel. Let rise 1 hour, or until dough has doubled in size. Punch down dough, cover, and let rise 30 minutes more.