Mince the 4 garlic cloves for the sauce and set aside separately from the 1 whole garlic clove you'll need later. Zest the lemon and set aside. Finely chop the fresh basil, separating the stems from the leaves. Crumble the vegetable stock cube. Preheat your oven to 200°C (about 400°F) so it's ready when you need it. Having everything prepped and your oven heating simultaneously means you won't have any idle time while the sauce simmers.

Heat 2 tablespoons olive oil in a large pot over medium heat. Add the minced garlic and cook for 2 minutes until fragrant, then stir in the frozen vegetables and cook for 3-4 minutes to warm through. Add the tomato purée and stir well to coat the vegetables, cooking for another minute to develop the tomato flavor. Pour in the passata, add the basil stems, crumbled stock cube, dried chillies, and 150ml water. Bring to a simmer and cook for 20-25 minutes, stirring occasionally, to allow the flavors to meld and deepen.

About 10 minutes before your sauce finishes simmering, bring a pot of salted water to a boil and cook the pasta 4 minutes less than the package instructions—this is crucial since the pasta will continue cooking in the oven and won't turn mushy. Drain the pasta well, reserving about 1 cup of the cooking water. As the pasta drains, stir the spinach and butter into your simmering sauce and cook for the final 10 minutes. I find that adding the spinach at the end preserves its bright color and fresh taste better than cooking it from the start.

In a small bowl, combine the ricotta cheese, lemon zest from Step 1, pecorino cheese, the whole garlic clove (finely minced), fresh basil leaves from Step 1, and a generous grind of black pepper. Mix gently with a fork until well combined but still creamy. This mixture will create a delicious contrast against the baked pasta beneath it.

Pour the cooked sauce from Step 2 into a large bowl with the cooked pasta from Step 3. Toss together gently, checking the consistency—if the mixture seems dry, add reserved pasta water a little at a time until it reaches a moist but not soupy texture. Transfer the pasta mixture into a 9x13 inch baking dish (or similar size) and spread it evenly. Dollop the ricotta mixture from Step 4 over the top in generous spoonfuls, then drizzle the remaining 1 tablespoon of olive oil over the ricotta to help it brown beautifully.

Place the assembled bake into your preheated 200°C oven and bake for 20-25 minutes until the top is golden brown and the sauce bubbles slightly around the edges. The pasta should be tender but not soft, and the ricotta topping should have a light golden crust. Remove from the oven and let rest for 5 minutes before serving—this allows the dish to set slightly and makes it easier to serve clean portions.