Preheat oven to 180°C

• Cook the pasta in a large pot of boiling, salted water for about 10 minutes or until they are almost cooked. The pasta should be al dente (frim to the bite) and not too soft. If overcooked the pasta will be too soft and can break when adding the stuffing. Drain and allow to cool in a single layer on a baking tray.
• While the pasta is cooling.
• In a large mixing bowl combine the thawed and squeezed out spinach leaves, ricotta cheese, cottage cheese, 120 grams mozzarella, parmesan cheese, salt, pepper (if using) and mix well. Use either clean hands to mix the filling or, if you have a stand mixer use that with the paddle beater attached. Taste for seasoning and adjust if necessary.
• Use a teaspoon to fill each pasta shell. It is very easy to overstuff the shells which will cause you to run out of filling, if this happens just remove a little filling from each of the filled shells and divide it amongst the remaining unfilled shells. <-- The stuffed shells can be frozen at this stage, please refer to notes below.
• Spread about 3-4 tablespoons of pasta sauce over the base of a baking tray or large casserole dish, then place the filled pasta shells (filling side up) in a single layer into the dish.
• Evenly spoon over the remaining pasta sauce, cover with a lid or foil and bake for 20 minutes.
• Remove from the oven and take off the foil, top with the remaining mozzarella, return to the oven and bake for another 10 – 15 minutes or until the cheese browns.
• Remove from the oven and allow to stand for 10 minutes before serving.