01 -
Slice Italian sausage, dice the onion, mince the garlic, and measure out pasta, broth, cheeses, and tomatoes.
02 -
Set a large skillet over medium-high heat. Add sausage slices and cook until browned evenly, about 5–6 minutes.
03 -
Add diced onion and minced garlic to the skillet. Cook until onion softens and garlic is fragrant, approximately 3 minutes.
04 -
Stir in penne pasta, chicken broth, and diced tomatoes (with juices). Ensure pasta is mostly submerged.
05 -
Bring mixture to the boil, then reduce heat to a gentle simmer. Cook uncovered, stirring occasionally, until pasta is al dente and most liquid has absorbed, about 12–15 minutes.
06 -
Fold in shredded mozzarella and grated Parmesan cheese. Stir until cheese is completely melted and the sauce is creamy. Season with dried Italian herbs, salt, and pepper to taste.
07 -
If using, add fresh spinach and halved cherry tomatoes, stirring until spinach wilts and tomatoes are warmed through.