Season the chicken pieces uniformly with salt, pepper, smoked paprika, and dried oregano.
Heat olive oil in a large deep-sided skillet or Dutch oven over medium-high heat.
Add chicken in a single layer and sear until golden brown on all sides, approximately 6 minutes. Remove chicken from the pan and set aside.
Reduce heat to medium and melt butter in the same skillet. Add the diced onion and sauté for 4 minutes until translucent.
Add the minced garlic and cook for 60 seconds until aromatic.
Stir in the rinsed rice and toast for 2 minutes, ensuring grains are coated in the residual fats.
Deglaze the pan with chicken broth, scraping the fond from the bottom. Return the chicken to the skillet.
Bring the liquid to a boil, then reduce heat to low. Cover with a tight-fitting lid and simmer for 15 to 18 minutes until the liquid is absorbed and rice is tender.
Remove lid and fold in the heavy cream, Parmesan cheese, and baby spinach. Stir until the spinach is wilted and the sauce has emulsified.
Remove from heat and allow the dish to rest, covered, for 5 minutes to stabilize the textures before serving.