01 - Bring a large pot of salted water to a rolling boil. Cook the cheese tortellini according to package directions until al dente. Drain well and set aside.
02 - While the tortellini cooks, season the diced chicken breasts generously with salt, pepper, and Italian seasoning. Heat olive oil in a large skillet over medium-high heat. Add the seasoned chicken and cook until golden brown and cooked through, 5 to 7 minutes. Remove the chicken from the skillet and set aside.
03 - In the same skillet, melt the butter over medium heat. Add the chopped onion and sauté for 2 to 3 minutes until softened and translucent. Add the minced garlic and cook for 1 minute until fragrant, stirring frequently to prevent burning.
04 - Pour in the chicken broth and deglaze the skillet, scraping up any browned bits from the bottom. Reduce the heat to medium-low and stir in the heavy cream and grated Parmesan cheese. Continue stirring until the cheese is fully melted and the sauce thickens slightly, about 3 minutes.
05 - Add the fresh baby spinach to the skillet and stir gently until wilted, about 1 to 2 minutes.
06 - Return the seared chicken to the skillet along with the cooked tortellini. Gently toss everything together until evenly coated in the creamy garlic sauce. Taste and adjust seasoning with additional salt and pepper if needed. Serve immediately, garnished with extra Parmesan and chopped fresh parsley.