Bring a large pot of generously salted water to a rolling boil for the pasta. While that's heating up, trim your broccolini and cut it into bite-sized pieces, then mince your garlic.

Heat the olive oil in a large skillet or Dutch oven over medium-high heat. Add the Italian sausage (casings removed) and cook, breaking it up with a spoon, until it's nicely browned and cooked through, about 6-8 minutes. Drain off any excess fat, leaving just a tablespoon or two in the pan.

Add the broccolini to the skillet with the sausage and cook for 3-4 minutes, stirring occasionally, until it starts to turn bright green and tender-crisp. Stir in the minced garlic and red pepper flakes (if using) and cook for another minute until fragrant.

Pour in the dry white wine (or chicken broth) and scrape up any browned bits from the bottom of the pan with a wooden spoon. Let it simmer for 2-3 minutes, allowing the liquid to reduce slightly.

While the sauce simmers, add the orecchiette to the boiling salted water and cook according to package directions until al dente. Before draining, reserve 1 cup of the starchy pasta water. Drain the pasta well.

Add the cooked pasta, grated Parmesan cheese, and lemon juice directly to the skillet with the sausage and broccolini. Pour in about 1/2 cup of the reserved pasta water. Toss everything together, adding more pasta water a tablespoon at a time if needed, until a light, glossy sauce forms that coats the pasta beautifully. Taste and season with salt and black pepper as needed.

Divide the pasta among bowls and serve immediately, with extra grated Parmesan cheese on top.