Put salted water on to boil for pasta and prepare pasta according to package directions, minus two minutes from al dante.
As you wait for the water to boil and the spaghetti to go in, heat oil in a large skillet over medium-high heat.
Season chicken pieces with salt and pepper and cook, searing each side, until just cooked through. Remove chicken to a platter and cover with foil to keep warm.
In the same skillet, add onion, olives and capers. Saute until onions are just translucent, about 3 minutes, and add garlic, oregano and red pepper. Saute until fragrant, 30 seconds to 1 minute.
Add wine and deglaze the skillet. Continue to cook until the wine is nearly evaporated. Add tomatoes and stir to combine.
The water should be ready by now, add the pasta and let the sauce reduce while the pasta cooks. Add 1/4 cup of parsley and salt and pepper to taste to the sauce.
When the pasta is 2 minutes from al dante, drain and add to the sauce. Stir the pasta in and continue to cook for 2 minutes.
Plate, top with remaining parsley and serve with chicken.
