A guy should probably start with the question of what does he want to eat for each meal.
There's quite a bit of overlap between what I'm trying to say and what this guy says, including the 2lbs and 4000 calories, 'cept I like oily canned fish and crackers and I prefer tang and recognize that alcohol is second only to fat in calorie density and a 151 Tang Sunset is nice after a day outside.
https://blackwoodspress.com/blog/37650/4000-calorie-ultralight-backpacking-meal-plan/
Hmm..perhaps a big bottle of whiskey has enough calories to sustain a man on a 3 day backpack hunt.