greek chicken pasta

2 cups penne pasta
1/4 cup butter, cubed
1 large onion, chopped
1/4 cup all purpose flout
1 can (14 1/2 oz) reduced sodium chicken broth
3 cups cubed rotisserie chicken
1 jar (7 1/2 oz) marinated quartered artichoke hearts, drained
1 cup (4 oz) crumbled feta cheese
1/2 cup chopped oil packed sun dried tomatoes
2 Tbsp minced freshe parsley