8ozzucchini (about 2 small or one medium), cut in half lengthwise and then into about ¼" half-moon pieces (I cut the very largest part into thirds lengthwise rather than in half, to keep the pieces about the same size)
14ozPolska kielbasa or smoked sausage, sliced in half lengthwise and then into about ¼" half-moon pieces
Cook pasta al dente according to package directions, then drain and return to pot.
Turn heat under that same pot to medium and stir in spinach, fire roasted diced tomatoes, and ¼ cup shredded Parmesan until cheese is melted and spinach is starting to wilt.
Meanwhile, heat olive oil in a 12" cast iron skillet over medium-high heat until shimmering. Add onion and cook for 3 minutes, stirring occasionally.
Add garlic and saute another 30 seconds, then stir in zucchini & kielbasa. Season the zucchini and sausage with seasoned salt, black pepper, crushed red pepper, and Italian seasoning, then continue sauteing over medium-high heat for 8-10 minutes or until zucchini is lightly browned, stirring occasionally.
Top your sausage and zucchini with ½ cup shredded Parmesan. Move your skillet into the oven and broil for 3-4 minutes until cheese is browned.
Remove the skillet from oven and add its entire contents (including the pan juices from the zucchini) to your pot of pasta, tomatoes, and spinach. Stir until everything is nicely combined, and spinach is completely wilted.
Serve your sausage & zucchini pasta with additional Parmesan to top (optional).
Notes
While much of this recipe does require hands-on time with its various steps of chopping, sauteing, boiling, draining, and broiling, it's all very straightforward! The timing also works out so that each step should feed nicely into the next, as long as you start your pasta water boiling around the same time as you start chopping your vegetables and sausage.