If it's calories and protein you're looking for I'll tell you what worked for me when, way back in my late teens, I was back packing out in the "wild country." I read an article about a mixture of dry ingredients that could be mixed with hot water to produce a great tasting hot drink that packed something like 45 grams of protein, 1000 calories, as well as substantial percentages of daily minimums for several vitamins and minerals.
I can't remember the exact quantities of the ingredients, but I think it was something like enough powdered milk to make a quart, one instant breakfast (chocolate), 1/4 cup "coffee mate," and 2 packets of swiss miss. I mixed that with 16 ounces of boiling water, and combined with occasional snacks of Brazil nuts, it was enough to get me through until mid afternoon. I remember I had to take my time to drink this, probably because of all the calories and protein, and would drink some immediately and sip on it through the next hour until it was gone.