1. Bring a large pot of salted water to a boil over high heat. Cook the pasta until al dente, according to the package directions. Reserve 1 cup of pasta water. Drain pasta and set aside, tossing the pasta through 2 Tbsp olive oil.
2. Meanwhile, heat a large frypan over medium heat and add 1 Tbsp of oil and the sausages. Cook, until browned and cooked through (about 8 minutes). Remove from the pan and keep warm.
3. Turn the heat down to medium low. Add an additional 1 Tbsp of oil and the garlic to the pan and cook until fragrant and soft (5 - 7 minutes)
4. Add the ricotta and parmesan to the pan. Adjust the heat to medium high, and cook stirring often, until thick enough to coat the back of a wooden spoon (about 2 minutes).
5. Stir through kale, 2 tsp of lemon juice (or to taste) and lemon zest. Cook, stirring occasionally, until kale has wilted and looks bright green (1 - 2 minutes).
6. Return the drained pasta to the pan and stir to combine. Add reserved pasta water 2 tablespoons at a time until the sauce is to your desired consistency.
7. Slice each sausage into 5 rounds, and stir through the pasta.
8. To make crispy herb crumb, add all ingredients to a small pan and heat over medium high, tossing until crumb is golden and sunflower seeds are toasted (1 - 2 minutes)
9. To serve, sprinkle the pasta with additional parmesan, herb crumb and a good grind of black pepper.