Heat olive oil in a large skillet over medium-high heat.
Season chicken pieces with salt, pepper, and oregano, then sear in the skillet until golden brown on all sides.
Add minced garlic and dry rice to the skillet, stirring for 2 minutes to toast the grains.
Pour in the chicken broth and bring the mixture to a boil.
Reduce heat to low, cover the skillet with a tight-fitting lid, and simmer for 15 to 18 minutes until the liquid is absorbed and rice is tender.
Remove the lid and stir in the heavy cream, parmesan cheese, and baby spinach.
Continue to cook uncovered for 2 to 3 minutes, stirring constantly until the cheese is melted and the sauce has thickened.
Rest for 5 minutes before serving.