The achievement where you have to heal 10k of damage with food. Still haven't got it.
The 30 games of caravan is easy, you just need to sit down and play it for an hour with frequent saving.
If you don't want to mess with it longer than you have to, you don't have to actually heal 10,000 damage. You can just drop your health below 100%, and if theoretically available, eat 10,000 HP worth of food at once and pop the achievement (if you're not in hardcoe mode, don't use water - it heals instantly). It's getting that much food that's difficult. Once you have it, dive beneath water, remove your rebreather, drown to near death, put the rebreather back on. Eat a bunch of food to heal, then use the wait function right after to cut down on time waiting.
General tips:
1.) Just remember that soda and water that isn't bottled doesn't count toward the achievement (bottled water does, but see above). The 188, Westside Co-Op, Follower's safehouse fridge, Nellis Mess Hall, and Sharecropper farms seem to have a proportionally-high amount of food, so try to include them every time you make 'the rounds' with merchants.
2.) Bump your survival skill, at least with a Lad's Life, before eating if you can.
3.) Arcade Gannon will increase the amount you heal from food, if he's your companion.
4.) You get 600 HP from a wasteland omelet (the Gourmand in the Ultra Lu sells them), at only 1 pound. Meat and crafted dishes in general give you much more HP overall as opposed to dropped items.
5.) Pip-Boy > Data > Misc > Challenges (Y) will track your progress.
6.) Watch your radiation levels if eating low-quality food and then 'waiting' to cut down time. It could kill you.