Step 1

In a large shallow dish, cover manicotti shells with boiling water and season generously with salt. Cover with foil or plastic wrap and set aside to soften slightly (about 7-10 minutes while you prepare your sauce).

Step 2

Heat the oil in a medium saucepan over medium-high heat. Sauté onion until transparent (about 3 minutes), then addd the garlic and cook until fragrant (about 30 seconds). Add the tomato sauce (Passata), water, paste and herbs. Bring to a boil, then lower the heat and simmer, covered, for 10 minutes.

Step 3

Stir in salt and pepper to taste. Use now, or store covered in the refrigerator for up to 3 days, or freeze for up to 2 months.

Step 4

Squeeze excess water from the thawed spinach.

Step 5

Combine filling ingredients in a bowl until well combined.

Step 6

Preheat oven to 350°F | 175°C.

Step 7

Spray the bottom of a 9 x 13-inch ovenproof baking dish with nonstick spray. Spread out about 2 ladles (or 1 cup) of the marinara sauce on the bottom of baking dish.

Step 8

Transfer filling mixture into a strong ziplock bag. Cut a hole in the bottom corner of the bag (see photos in post, or use a piping bag).

Step 9

Once manicotti tubes have softened slightly but are still firm to the touch, use a slotted spoon to transfer them from the boiling water to a plate. 'Pipe' filling into manicotti tubes and arrange them in a single layer over the sauce in the baking dish. Top with remaining sauce and cheese.

Step 10

Cover with foil and bake for 30 minutes. Uncover and bake for a further 10-15 minutes, or until pasta shells are cooked through.Serve immediately.