Believe it or not cold hamburger is pretty good. I took it for lunch one day and it was fine. That would be something you could make ahead. Same goes for bacon, it is good cold too. Boiled eggs travel well in a lunch box. Meat sticks and lunch meats are pretty good for a lunch. A really good quality steak cut in thin strips after cooked is good cold too.

If you don't like vegetables (I agree they do cause gas) you might watch some of the carnivore youtube channels for ideas.

https://www.youtube.com/watch?v=ZqtXTP2BDgc&list=PL48jnTudSMf_Qiip-b6rMgS_7fL6t7v1N

Wife and I have plain yogurt with a few blueberries and chopped pecans for a fairly low carb desert.

John