I like to backpack in the high mountains of Colorado and New Mexico. My lunch comprises (1) GORP, (2) Longhorn Colby cheese on rye-crisp, (3) fruit roll-ups, (4) beef jerky, (5) chocolate bar. I don't always take all of this, but that's a start anyway. The GORP is a mix of granola, trail-mix, and M&Ms. Usually, I mix about 1.5 LBS of granola (french vanilla and almond granola), 1 LBS trail mix, and about 12 oz of M&Ms. The trail mix usually has a mix of nuts such as peanuts, almonds, hazelnuts and dried fruits such as raisins, chopped dates, and other dried fruits and maybe some seeds such as sunflower seeds. I really love the GORP. I will keep a bag of this in the side pocket of my backpack and at rest stops I will fetch out this bag and eat a couple of handfulls to keep my spirits and my energy up. There are now cheese sticks available in stores where you can buy individually wrapped pieces of cheese about the size of an ink pen. Thus, you don't have to fuss with a 1 LBS block of cheese but can carry the quantity you'll likely eat and not have to worry about keeping the remaining cheese fresh. This kind of cheese doesn't need to be highly refrigerated -- it tends to tolerate being out of the refrigerator pretty well, just keep it wrapped up or it will dry out.
