Bring a large pot of salted water to a boil. Add the fettuccine and cook until al dente, about 10 minutes. Reserve 1 cup of pasta cooking water, drain, and toss with olive oil.

In a large skillet, cook the chopped bacon over medium heat until crispy, about 5–7 minutes. Remove with a slotted spoon and set aside, leaving the fat in the skillet.

Melt 1 tablespoon of butter in the skillet with bacon fat. Sauté the shredded chicken for 3–4 minutes until heated through. Keep warm and set aside.

Add 2 tablespoons of butter to the skillet, melt, and sauté the minced garlic for 30 seconds until fragrant.

Pour in the white wine, simmer and reduce by half for about 2–3 minutes.

Stir in chicken stock, heavy cream, sun-dried tomatoes, red pepper flakes, and Parmesan cheese. Cook for about 4 minutes until sauce thickens.

Add the shredded chicken, spinach, and cooked fettuccine. Toss gently for about 2 minutes until spinach wilts and pasta is coated in the sauce.

Remove from heat, garnish with crispy bacon and parsley. Serve immediately with extra Parmesan cheese if desired.