Heat 2 tablespoons oil in skillet. Add spinach, bacon and 1/4 teaspoon salt; sauté until softened, 5 minutes. Remove from heat.
Combine 1 cup flour, yeast and remaining salt in bowl.
Heat water and remaining oil in saucepan until very warm (125°F to 130°F). Gradually beat water mixture into flour mixture. Beat in 1-1/2 cups flour with wooden spoon, 1/2 cup at a time, to make soft dough.
Knead dough on floured surface until smooth and elastic, 10 minutes, working in remaining flour as needed to prevent sticking. Shape into ball. Cover; let rest 10 minutes.
Roll dough out on floured surface into 15 x 11-inch rectangle. Fit in greased 15 x 11 x 1-inch jelly-roll pan, gently pushing dough up into corners. With finger, make indentations all over surface of dough, pressing almost to bottom of pan. Scatter spinach over top. Sprinkle with cheese. Cover with plastic. Let rise in warm place until almost doubled in bulk, 30 minutes.
Bake in 400°F oven for 20 to 25 minutes, until lightly browned. Cut into 12 pieces. Serve warm.