Vitamin B12. Check. Iron. Check. High Cholesterol? Awwwwww........Chicken Liver. I eat them.
Do you?

Many people enjoy chicken liver as chicken liver pate. For me, I enjoy the
Chinese Braised Chicken Liver (卤鸡肝) that my friend makes. She cooks it for her growing kid and two of us ladies, also get to enjoy it the same time (Another kid-friendly recipe you might want to try:
Chicken Liver with Tomato Noodle Soup). It has got the
iron we need as well.
Some may consider Offal-type food to be high-cholesterol but it is not as if you are eating offals such as chicken liver everyday, so I personally think it is ok if it is the cholesterol you are worrying about. Further, of all the offals and to choose among poultry/meat livers - chicken liver is considered one of the better of offal to consume in terms of good quality nutrition content per serving.
Vitamin B12 (one of the most common Vitamin B deficiencies for most of us) is also known as cyanocobalamin or cobalamin. This vitamin is necessary for the central nervous system to function properly. It helps in the formation of red blood cells. It is also necessary for proper development and growth in children. It is only found in animal sources including: Meat, Liver, Kidney, Eggs, Milk and some Dairy Products.