Before starting, preheat the oven to 450˚F. Wash and dry all produce. Garlic Guide for Step 5 (dbl for 4 ppl): 1/4 tsp mild, 1/2 tsp medium and 1 tsp extra! 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. While water comes to a boil, cut tomato into 1/2-inch pieces. Peel, then cut half the onion into 1/2-inch pieces (use whole onion for 4 ppl). Roughly chop spinach. Cut mozzarella into 1/2-inch pieces. Peel, then mince or grate garlic.

Add penne to the boiling water. Cook uncovered, stirring occasionally, until tender, 10-12 min. Reserve 1/4 cup pasta water (dbl for 4 ppl), then strain and return penne to the same pot, off heat.

Heat a large non-stick pan over medium heat. When hot, add 1 tbsp oil (dbl for 4 ppl), then onions. Cook, stirring often, until softened, 2-3 min. Add tomato sauce base, tomatoes, spinach, half the garlic and 2 tsp Italian Seasoning (dbl for 4 ppl). Cook, stirring often, until fragrant, 1-2 min.

Add 2 tbsp oil (dbl for 4 ppl), remaining Italian Seasoning and 1/4 tsp garlic to a medium bowl. (NOTE: Reference garlic guide.) Add mozzarella. Season with salt and pepper, then gently stir to coat. Halve ciabatta. Arrange ciabatta on an unlined baking sheet, cut-side up, then top with half the mozzarella. Toast in the middle of the oven until cheese melts, 3-4 min. (TIP: Keep an eye on them so they don't burn!)

Add sauce, reserved pasta water, sun-dried tomato pesto and half the Parmesan to the pot with penne. Season with salt and pepper, to taste, then stir to coat, 1-2 min. Cut garlic ciabatta into triangles. Divide penne between plates. Top with remaining mozzarella. Drizzle balsamic glaze over top. Sprinkle with remaining Parmesan and chili flakes, if desired. Serve garlic ciabatta alongside.