In a boiling pot of salted water cook the pasta according to the directions on the package.
Season the chicken with salt and pepper.
In a nonstick pan, heat the oil over medium heat; saute the onion and garlic for about 3 - 4 minutes. Add in the chicken and brown.
Once the chicken has a golden brown, add the artichoke, olives, oregano, and tomatoes; saute for 3 minutes. Then add the broth, lemon juice, and butter; bring to a simmer; about 5 to 8 minutes. Taste and adjust the season with salt and pepper if needed. Toss in the pasta, garnish with feta and parsley. Serve with crusty bread.