Bring a large pot of salted water to a rolling boil and add the fettuccine. Cook according to package directions until al dente, about 8-10 minutes. Before draining, reserve 1 cup of pasta water—this is essential for your sauce. Drain the pasta but don't rinse it; the starch helps the sauce cling beautifully.

While pasta cooks, heat the olive oil and butter in a large skillet over medium heat. Once the butter foams, add your minced garlic and let it get fragrant for about 1 minute—don't walk away or it'll burn. You'll know it's perfect when you can really smell it and the kitchen starts smelling amazing.

Pour in the heavy cream and bring it to a gentle simmer over medium heat. Let it bubble softly for 2-3 minutes while you get your chicken and spinach ready. The cream should look slightly thickened when you tilt the pan.

Add the diced chicken and cooked fettuccine directly to the cream sauce. Toss everything together gently using tongs so you don't break the pasta. The creamy garlic pasta recipe starts coming together right here—it's kinda magical how quickly it happens.

Sprinkle in the Parmesan cheese, salt, pepper, and oregano while tossing continuously. Add the spinach and keep tossing until it wilts completely into the sauce. This takes about 2 minutes, and you want everything evenly coated before moving on.

If the sauce seems too thick, splash in some reserved pasta water a little at a time—start with 1/4 cup. The sauce should coat the pasta but still flow slightly on your plate. I usually end up using about 1/2 cup depending on how much cream I used.

Taste and adjust seasoning if needed (sometimes I add a pinch more salt), then transfer to plates. Garnish with fresh parsley and extra Parmesan if you're feeling fancy. Serve immediately because this dish is best when it's still steaming.