Preheat oven to 400°; boil a large pot of salted water, add half the box of pasta + cook 8-10 min or until al dente, then drain + return to pot

Meanwhile, heat 1 tbsp oil in large skillet over med-high + sauté half the spinach + salt/pep 1-2 min until wilted; add remaining spinach + cook 1-2 min more until all spinach is wilted

Add ¼-½ cup sauce, spinach + salt/pep to pasta; toss to coat noodles

Transfer pasta mixture to a lightly oiled baking dish + sprinkle on 3-4 torn slices of cheese (or more!); bake for 15-17 minutes until cheese is melted + bubbling-YUM!