In a shallow bowl, mix together flour, paprika and salt and pepper. Coat chicken pieces with the seasoned flour.
Heat oil in a large frypan over medium heat and saute chicken until light golden brown (about 45 seconds each side). Remove chicken from frypan and set aside.
To frypan, add mushrooms, lemon juice and chicken stock. Simmer until a smooth, light sauce develops. Season with garlic powder. Return chicken to the frypan and simmer until chicken is no longer pink and juices run clear. Stir in artichoke hearts and remove from heat.