Gather all ingredients.
Mix together oregano, salt, and pepper in a small bowl. Rub spice mixture all over chicken breasts. Melt butter in a skillet over medium heat.
Cook chicken in butter until lightly browned, 3 to 5 minutes per side.
Place chicken in a slow cooker.
Mix water, lemon juice, garlic, and bouillon in the same skillet; bring to boil.
Pour mixture over chicken in the slow cooker.
Cover and cook on Low for 6 hours or High for 3 hours. Add parsley to the slow cooker 15 to 30 minutes before the end of cook time.
Serve hot and enjoy!