First, heat the olive oil in a large pot over medium heat. Once hot, add the spicy Italian sausage. Use a spatula to break it apart as it cooks, letting it brown for about 5 minutes. The sizzling sound is the first hint of the flavor explosion to come!

When the sausage is beautifully browned, toss in the chopped onion and minced garlic. Sauté for another 3-4 minutes. The onion should become translucent, and you’ll catch the delightful scents filling your kitchen. At this point, you can add the crushed red pepper flakes if you want a bit of a kick.

Next, add the sliced zucchini to the pot. Stir everything together and let it cook for another 5 minutes until the zucchini begins to soften but still holds its shape. You want that lovely texture!

Now, it's time to add the bucatini pasta to the mixture. Pour in the low-sodium chicken broth. Make sure the pasta is submerged. Bring the mixture to a gentle boil, then reduce the heat and cover. Let it simmer for about 10-12 minutes. Keep an eye on it, stirring occasionally to ensure nothing sticks to the bottom.

After simmering, remove the pot from the heat. Stir in the freshly grated Parmesan cheese and lemon zest. The cheese will melt beautifully, creating a creamy sauce that coats each piece of pasta and zucchini. Taste for seasoning, adding salt and pepper as necessary.

Your one pot pasta with zucchini and sausage is ready to serve. Ladle the pasta into bowls and sprinkle a little extra Parmesan on top, if desired. Grab your loved ones and dig in!