Season chicken thighs with salt, pepper, garlic powder, and paprika.
Heat olive oil in a large pot or Dutch oven over medium-high heat.
Sear chicken thighs on both sides until golden brown. Remove chicken and set aside.
Add chopped yellow onion to the pot and sauté until softened, about 5 minutes.
Add minced garlic and cook for another minute until fragrant.
Stir in the orzo and toast for 1-2 minutes.
Pour in the lemon juice and chicken broth, scraping up any browned bits from the bottom of the pot.
Bring to a simmer, then return the chicken thighs to the pot.
Cover and cook for 10-12 minutes, or until the orzo is al dente and the chicken is cooked through.
Stir in the heavy cream and grated parmesan cheese until the sauce is creamy.
Wilt in the spinach, stirring until just combined.
Serve immediately.
