Before starting, preheat the broiler to high. Add 10 cups water and 2 tsp salt to a large pot (use same for 4 ppl). Cover and bring to a boil over high heat. Wash and dry all produce. Halve zucchini lengthwise, then cut into 1/2-inch half-moons.Roughly chop spinach.

Add rigatoni to the boiling water. Cook, stirring occasionally, until tender, 10-12 min. Reserve 1/4 cup (1/2 cup) pasta water, then drain and return rigatoni to the same pot, off heat.

Meanwhile, heat a large non-stick pan over medium-high heat. When hot, add beef and zucchini to the dry pan. Cook, breaking up beef into smaller pieces, until zucchini is tender-crisp and no pink remains in beef, 5-7 min.\*\*Carefully drain and discard excess fat.

Add half the Italian Seasoning (use all for 4 ppl) and half the garlic salt (use all for 4 ppl) to the pan with sausage and zucchini. Season with pepper. Cook, stirring often, until fragrant, 1 min. Add crushed tomatoes and reserved pasta water. Cook, stirring often, until warmed through, 1-2 min. Add spinach, cream cheese and half the mozzarella. Cook, stirring often, until spinach is wilted and sauce is smooth.Season with salt and pepper, to taste.

Meanwhile, grease an 8x8-inch baking dish with 1/2 tsp oil. (NOTE: For 4 ppl, grease a 9x13-inch baking dish with 1 tsp oil.) When sauce is done, add to the pot with rigatoni, then stir to coat. Transfer rigatoni mixture to the prepared baking dish, then sprinkle remaining mozzarella over top.Broil in the middle of the oven until cheese melts, 3-4 min. (TIP: Keep your eye on cheese so it doesn't burn!)

Let rigatoni bake cool for 2-3 min before serving.Divide between plates.