I like to travel light and be able to make meals underway. I am seldom gone for a week at a time though.
Every option you consider is skill dependent of course... YMMV.
I like to Carry a frying pan, knife, and mortar/pestle. The knife and mortar/pestle are very small and lightweight. Keep the pan in the wagon.
Butcher every now and then as you do now (or fish for meat). Forage/Botanize a few tiles (enough for 2 veggies and 2 herbs at least). This goes much faster at higher skills, but doesn't take long at low skills.
Chop every vegetable/herb that can be chopped, mince your one piece of meat, crush all your paprika/nutmeg/turmeric/etc throw in any nuts you might harvest (needs a sickle and seasonal) and throw it into the pan over a 1 kindling fire. Just let it cook while you do whatever you do after you park the wagon.
If you only have part of one crate for space in your wagon I'd take kindling with you so you don't have to mess with chopping trees for a quick meal.
Meals keep your bars up higher than salad. You can use salt or waxed paper to make them last longer (not necessary just to get CCFP up). Take the tools and live off the land; Enjoy!
Added: A lunchbox/picnic basket is nice to keep your meals hot, but I wouldn't bother unless you use affinity meals and want the most effect from eating them easily on the go.