In a mixing bowl, generously coat the sliced chicken breasts with Cajun seasoning, ensuring all pieces are evenly seasoned for maximum flavor.
Heat olive oil in a large skillet over medium-high heat. When the oil is shimmering, carefully add the seasoned chicken to the skillet. Cook for about 4-5 minutes, or until the chicken is nicely browned and cooked through. Once done, transfer the chicken to a plate and set aside.
In the same skillet, reduce the heat to medium. Add the minced garlic and sauté for approximately 30 seconds, or until it becomes fragrant but not burnt.
Pour the chicken broth into the skillet, bringing it to a gentle simmer. Gradually stir in the heavy cream, allowing the mixture to bubble softly for a few minutes to blend the flavors.
Add the fettuccine pasta to the simmering sauce. Cook according to package instructions, stirring occasionally, until al dente (typically around 8-10 minutes).
In the final 2 minutes of the pasta cooking, fold in the halved cherry tomatoes and fresh spinach.
Once the pasta is al dente, return the cooked chicken to the skillet. Gently toss everything together until well mixed and heated through.
Remove the skillet from heat. Stir in the grated Parmesan cheese, mixing until the sauce is creamy and well combined. Taste, and adjust seasoning with salt and freshly ground black pepper as needed.
Plate the creamy Cajun chicken pasta immediately, and sprinkle with chopped fresh parsley for a pop of color and added freshness if desired.
Notes
Serve immediately for the best flavor and texture.