Slice chicken sausage links into half-inch rounds and set aside. Heat olive oil in a large skillet over medium-high heat until it shimmers. Working in batches if needed, brown the sausage pieces for 3-4 minutes per side until golden, then transfer to a plate.
Add diced onion to the skillet and sauté for 2-3 minutes until softened and fragrant. Stir in minced garlic and cook for another 30 seconds until aromatic. This creates the flavor foundation for your entire cozy fall sausage skillet dinner recipe.
Add diced bell peppers and butternut squash to the skillet, stirring constantly for 4-5 minutes. The vegetables should begin releasing their natural juices and softening slightly. Pour in the chicken broth and canned tomatoes with their liquid, scraping any browned bits from the skillet bottom.
Return the sausage to the skillet and add dried thyme, sage, salt, and black pepper. Stir everything together and bring to a gentle simmer. Reduce heat to medium and simmer for 8-10 minutes until the butternut squash becomes tender and flavors meld beautifully.
Add diced zucchini in the final 4 minutes of cooking so it remains slightly firm and doesn't turn mushy. Taste and adjust seasonings as needed. Finish with fresh chopped parsley right before serving for brightness and color.