Look into keto. I go on multi-week bike expeditions and bringing food that's 70% fat really saves space and takes far less time to eat. One of my favorite recipes is 4:4:2:2:1 peanut butter: coconut oil: dark chocolate: whey protein: coconut flour, or there about. Tastes vaguely like a Reece cup, without being disgustingly sickeningly sweet, about a hundred calories a bite. Lots of other stupidly dense foods that save a ton of time eating.