01 - Bring a large pot of salted water to a rolling boil. Cook the cheese tortellini according to package directions until tender. Drain through a colander and set aside.
02 - While the tortellini cooks, heat olive oil and butter in a large skillet over medium-high heat. Add the chicken pieces, season with salt, pepper, and Italian herbs if using. Sear until golden brown and cooked through, approximately 6 to 8 minutes. Transfer the chicken to a plate and set aside.
03 - Reduce the heat to medium. In the same skillet, add the chopped onion and cook until softened, about 3 minutes. Add the minced garlic and sauté until fragrant, approximately 30 seconds.
04 - Pour in the heavy cream, cream cheese, and grated Parmesan. Stir continuously and simmer gently until the cheeses have fully melted and the sauce is silky smooth, about 2 to 3 minutes.
05 - Add the chopped spinach to the skillet and cook, stirring gently, just until wilted, about 1 to 2 minutes.
06 - Return the seared chicken and cooked tortellini to the skillet. Toss everything together gently until evenly coated in the creamy garlic sauce. Adjust seasoning with additional salt and pepper as needed. Serve immediately, garnished with extra Parmesan and fresh parsley if desired.