Add garlic, sliced leek and lemons to a baking dish. Drizzle generously with olive oil and add rosemary, chili flakes, parsley seasoning, salt and black pepper.
Roast at 350°F (180°C) until everything is soft, caramelized and golden.
Cook pasta until al dente and save plenty of pasta water.
Add the roasted garlic, leek and lemons to a blender. Blend until creamy. Add pasta water little by little to make the sauce smoother and less intense.
Mix the hot pasta with the sauce and finish with lots of parmesan.
