Bring a pot of salted water to a boil, cook fettuccine until al dente.
Meanwhile, preheat skillet over medium heat. Season chicken thighs with salt and pepper. Coat with panko. Add 2 T olive oil to your pan, allow to heat up, then add your chicken, cooking until browned on both sides and cooked through, approximately 10 minutes, flipping half way through. Remove from pan.
Add red pepper and garlic to the pan, sautéing until red pepper has softened slightly and garlic has browned, approximately 2 minutes. Melt butter in pan, whisk in flour and cook for 1-2 minutes. Slowly pour in the wine, bring to a boil, scraping up browned bits from the bottom of the pan. Slowly pour in cream and half-and-half, stir to combine. Bring to a simmer and allow to cook until slightly thickened. Stir in parmesan and spinach. Sauce is finished when spinach is fully wilted. Slice chicken thighs. Serve pasta with sauce and topped with chicken.