Need some advice on nutrition and foods for weight gain.

My ex has been diagnosed with pancreatic cancer. He has undergone chemo and surgery and was on track for a good recovery when it was discovered that he had stomach cancer. The surgery for that was successful, but he was recently told that cancer has shown up in his spine. He has had radiation for that, but he is still waiting for results. He goes in next week for a scan and a visit with his oncologist. The news so far is not encouraging.

In the meantime, he has suffered a dramatic weight loss and now weighs in at 121 lbs. on a 6' frame. Many of the foods he used to enjoy don't taste good to him now and he doesn't have much appetite. His wife is battling her own health issues and is not able to do much more than just warm things up at this point. He is drinking Boost, or a similar product, twice a day but continues to lose weight.

My daughter would like to fix some single serve nutritious meals for him that might help him to gain a little weight. Does anyone have suggestions as to how we could get the maximum punch in the smallest portions? Something that could be stored in the freezer to just heat and eat would be the most convenient for him.

Any advice would be much appreciated.