Bring a pan of salted water to the boil and add the pasta. While it’s cooking, zest and juice the lemons. Place the crème fraîche in a large bowl and add the Parmesan, and generously season with salt and pepper. Stir through the zest and juice. In a pan, quickly sauté the onion and garlic till soft. Add in the diced zucchini and chilli and cook for just 3 minutes before adding in the sliced asparagus. Cook for just 2 minutes. Finally, add in the baby spinach leaves and the crème fraiche mixture and heat through. Stir in the pasta, grind in some fresh black pepper and serve.