For the protein powder, you can premeasure some powdered milk to go with. I suggest adding a little sugar to it as the powdered milk seems to be an acquired taste. For deep backcountry where weight/distance are issues I like to carry ramen noodles. They are easily prepared in water that is barely warm, so you can get long life from a fuel canister. If you try beans/rice/other pastas it takes a bit of boiling to get them ready to eat and uses up fuel. Other than that, lots of bars. My favorite right now being the Snickers Marathon bars--280 cal with 21 g of protein.