Q. What's a calorie-dense, easy-to-eat food in the cupboard?

Snowed in; partner's sick. He seemed to have a cold last week, but symptoms seem more flu-like (including nausea and vomiting) this week. He's weak and needs more calories. Have limited supply of Ensure; he needs something easy to swallow that's calorie dense that I can concoct from items we have here. Ideas? Thanks!