This is the third time I've moved cross-country by car in three years, so I'm just going to tell you what I've done.
Before the Move
First of all, we pack up the kitchen almost last. About a month before the move date, I take inventory of all the food I want to use up before the move, and I make a month-long dinner menu to try to use up as much as possible and avoid buying extra. (Normally I make a dinner menu at the beginning of each week.) I fill the last week or so up with frozen dinners. I start stocking up a couple months before by freezing sufficient leftover portions of our dinners. This is easy for me to do at the moment, as I only have to feed two adults and a 4-year-old. Other families might need to do some dedicated freeze-cooking, or make double portions some nights. With frozen dinners planned for the last week, I can pack up the kitchen without worrying about cooking at the same time. The last day or two before we leave, we'll eat dinner out or pick up something to go.
Things I leave out of packing up the kitchen and bring in the car:
*my deep skillet and lid
*large plastic serving spoon
*wire cheese slicer
*small plastic cutting board
*scrub brush and dish soap
Those allow me to heat up the frozen dinners on the stove and also make sandwiches, breakfast, tea, etc. (I can also hard boil any leftover eggs before we leave.)
While we normally do not use paper towels, paper napkins, paper plates, plastic cutlery, or disposable cups, we use all of these things liberally during our moves, with no guilt. I start using these when we start eating the frozen dinners. Then around the beginning of the last week before the move, everything in the kitchen is washed and ready to be packed up.
During the Move
During the drive to our new home (the last two years we had 5 days of driving), we make two meals a day and snacks from what we've brought with us, and eat out for the third meal (whether it's lunch or dinner depends on the day's driving schedule).
Here is what I typically pack in the car:
In a medium-sized cooler:
*cheese (string, block, and/or slices)
*hard boiled eggs
*bottles of kombucha
*cod liver oil
In a box or other receptacle:
*raisins, dried cranberries, dried cherries, etc
*bread (sometimes bagels)
*crackers, chips, rice cakes, etc
*ranch dressing mix (I find this tasty on sandwiches and sad fast-food salads)
*apples, bananas, oranges, etc
*fruit leather, Larabars, etc
*a sturdy Tupperware-type container with the paring knife and cheese slicer (for chopping things and assembling sandwiches)
*disposable plates, napkins, cutlery
*our regular vitamin supplements
Then we also have these things, which we mostly just take out in the hotel rooms:
*coffee and one of these
*travel coffee mugs
We eat toast, hard boiled eggs, tea, coffee, and fruit for breakfast. Sandwiches, chips, and fruit for lunch or dinner.
After the Move
This might be the hardest part for me. First of all, unpack your kitchen almost-first (I think my mental list goes: beds, couches, some of Lucy's toys, kitchen).
One box at a time is best, I find. Put the stuff approximately where you think it will live, but it doesn't have to be perfect. You can rearrange things later. You just want it all out of the boxes so you'll have room to move around and cook.
Then there's the first trip to a strange grocery store. Plan that for the time of day you have the most energy, after you've eaten, and plan for it to take five times as long as it should. Of course make a list before you go. Then you'll have to go back two days later for the stuff you forgot to put on your first list.
Then I personally start the long process of building kitchen momentum back up. By that I mean, getting my freezer stashed with cooked brown rice, cooked pinto beans, chicken broth, etc; starting to make homemade bread again; starting to put away freezer meals; finding a kombucha scoby. Once you get going, it's easy to keep going, but staring at an empty freezer at first is so depressing!
[First meal cooked in the new house this time. It feels so great to cook again after a week or more of fast food!]