Cook orzo pasta according to package directions until al dente. Drain and set aside.
In a large pan or skillet, heat olive oil over medium heat.
Add onions and chicken, then sprinkle in seasonings. Let cook for a few minutes before adding in the minced garlic.
Cook until the chicken is no longer pink. Transfer chicken to a plate.
Into the same skillet, add in chicken broth, lemon juice, Dijon mustard, and cornstarch. Stir to combine and let cook for 2-3 minutes.
Stir in heavy cream and sun-dried tomatoes. Let come to a slight boil then add the Parmesan cheese. Let cook until the cheese is melted.
Add chicken back into the skillet and let cook for 5-6 minutes until chicken is completely cooked through and mixture is hot.
Now, stir in spinach and let cook until spinach starts to wilt.
Add in orzo pasta, stir to combine and serve.
Notes
Cook the orzo al dente: Since the orzo will be stirred into the warm sauce at the end, cooking it al dente helps keep it from becoming too soft.
Cut the chicken evenly: Cutting the chicken into roughly 1-inch pieces helps it cook more evenly.
Don't skip the seasonings: The combination of paprika, basil, oregano, garlic salt, black pepper, and Slap Ya Mama gives the chicken a lot of its flavor.
Use the same skillet: Cooking the sauce in the same skillet as the chicken helps carry all those savory flavors into the sauce.
Don't rush the Parmesan: Let the cheese melt fully into the sauce before moving on to the next step.
Keep an eye on the cream: Bring the sauce to a slight boil rather than letting it aggressively boil.
Add the spinach near the end: Baby spinach wilts quickly, so there's no need to cook it for long.
Stir the orzo in last: Adding the cooked orzo at the end helps keep the pasta from becoming overly soft.