Prep the chicken: Pat the chicken dry with paper towels. Toss with salt, pepper, paprika, onion powder, and oregano until evenly coated.
Sear the chicken: Heat olive oil in a large skillet over medium-high.
Add the chicken in a single layer. Cook 5–7 minutes, stirring a few times, until browned and just cooked through. Transfer to a plate and cover loosely.
Sauté the garlic: Lower heat to medium.
If the pan looks dry, add a small splash of oil. Add minced garlic and cook 30 seconds until fragrant, scraping up browned bits.
Build the sauce: Stir in chicken broth and bring to a gentle simmer. Whisk in the cream cheese cubes a few at a time until smooth and melted.
Finish the cream base: Pour in heavy cream and add Parmesan.
Stir until the sauce is silky and slightly thickened, 2–3 minutes. Taste and adjust salt and pepper.
Add the greens: Stir in spinach and let it wilt, about 1 minute. If using, add a pinch of red pepper flakes.
Combine and brighten: Return the chicken and any juices to the skillet.
Toss to coat. Simmer 1–2 minutes to heat through. Stir in lemon juice if you like a fresh pop.
Serve: Garnish with chopped parsley.
Serve hot with a low-carb side like cauliflower rice, zucchini noodles, or roasted broccoli.