magnesium question

My husband was recently in the ER with chest pains and other problems. after hours of testing and monitoring they found that he was seriously low on magnesium. they gave him some in an IV and told him to take a supplement and eat foods that are high in magnesium. I have found lists of foods to make I have a question about the spinach. does it have to be boiled? he will not eat it boiled, he will eat it in enchiladas, casseroles,salads, raw and cooked.. just not boiled. maybe I could steam it? The only way I have ever cooked with spinach before is putting it into recipes. I need help! I need to know if I am doing ok with it or not. I dont want to ruin the nutritional value of the food. PLEASE HELP

I'd recommend eating it as a salad. Raw. Use spinach instead of lettuce. It tastes great & is healthy.

Also, steaming is better than boiling.