Depending on how long the sit is and distance depends on what we eat and take, we drive to our UK sits and to date have not managed any Overseas sits as yet.
If we are just a couple of nights and if it is close by, I grab a load of Meals that I have in the Freezer, when ever I cook, I always cook extra, if it doesn’t get eaten, I freeze it for a day that I just can’t cook at Home, a House sit or Hubby gets to live off them while the Kids and I are away on Housesits.
If it is a bit longer and not too far away, I will take as much as I can from home.
IE we are on a sit atm 10days, I had loads of fruit and veg still from Christmas and New Year, so I started with all that, then worked around what I can make with it all, roasts, soups, pasta sauces etc, so packed herbs and spices, just basic ones, pasta, rice, then flour, sugar, cereal, milk, bread/rolls/wraps, spread, I set the challenge for this sit to not go shopping only for bread as I knew we would run out and I’m nursing a torn knee ligament, awaiting surgery and in a bucket load of pain, so while i want us to eat healthy, i am keeping it all very simple atm, so I said to the Kids “we can drive to the closest petrol station and get fresh bread when we need it and that’s it, we are eating all this food” we are doing pretty good so far.
I use “too good to go” and “olio” quite a lot, especially when on a House sit, if we are away we use them quite a lot. We had a sit last year for 3 weeks and apart from our Vegan sub items like Nutritional Yeast (which I know you could go and buy it) we took those items, I took uncooked beans/pulses/pasta/rice they all go in zip lock bags and get packed around other items in the boot, we didn’t buy breads once, or Banana’s, actually most of our F&F, we got it all from within a 10min walk for the house we were staying at from Olio and at least 3 times a week we had meals from “too good to go” and some treats from Costa Coffee, I went to the supermarket once when we got there and got tinned tomatoes, tomato puree’s, spread, oil, s&p, seasonings and we lived off what we could pick up free from Olio or Too good to go, the Kids and I enjoyed the challenge and we agreed that If you lived in a built up area or a city, you could potentially live like this, though you might be eating a lot of bread items (lol)
Sometimes if it is a couple of nights, I will take spaghetti and beans and we have that on toast for dinner or soup with toast.
I understand the not wanting to have to cook it all then wash a heap of pots and pans, I suppose it also depends on what you like to eat and if you just want something simple or take some tinned vege/foods etc.
You could get a tin of white beans (don’t drain them, use the whole lot the aquafaba thickens to the soup beautifully) a tin of potatoes, a tin of mixed veg (sorry IDK if they exist) a tins of carrots and other veg’s (drain the liquid off them though) stock cubes, tin of tomatoes and small bag of pasta and make a minestrone type soup, you only need a shake of Italian style herbs (I’m sure the HO wouldn’t mind you using a little of whatever they have) some Garlic too and you have a one pot soup possibly 2-3 meals with some fresh bread.
Happy sitting.
I usually cook 4-5 nights a week with 2 meals out a week. I usually go for cheaper lunchtime deals as my remote work is flexible.
I mix things up with an easy meal or 2 (pizza or ready meal) along with cooking from scratch.
We eat out once a week and cook every other day. Mostly healthy- Pizza on Sundays!
My very first sit was 4 days over Christmas and there was no way I was going to cook, and the village pub has closed down, so I treated myself to some frozen meals from Cook. I had a real treat though because lovely neighbours invited me for Christmas lunch 
My second sit was 6 days over New Year so I took along the meal I didn’t use over Christmas plus a few bits to make simple meals. Although I ate in the village pub one day (not cheap!) I’m glad I didn’t plan to eat there often because that was the only day it was open!
I’m looking forward to my next sit, only 3 days, and I’m batch cooking some meals to freeze so I have something to take with me (I’ve checked that there is a microwave).
One of the things I love about traveling is the food. Like when I’m in the U.K., I try to have afternoon tea, Sunday roast, full English (or Irish or Scottish). When I’m on the West Coast in the U.S., even the meal deliveries are way better than generally elsewhere in the U.S. That’s because in places like San Francisco or Seattle, there are more people willing to spend on food, so they support a more robust restaurant ecosystem. I take advantage of that.
And different places have different advantages. Like when I’m in San Diego, I can get homecooking-style food from Guam, because many U.S. military folks are based in SD and stay after their service.
In U.S., there also have been various immigration patterns that have ended up creating different pockets of cuisine. It pays to look for such if you’re open to eating out or ordering delivery.
The San Francisco Bay Area has better Indian food than many parts of the country, for example. That’s because tech has led to many Indians settling there. LA and Atlanta (Duluth) have terrific Korean food, because of their Korean-American concentrations. Dearborn, Michigan, has great Middle Eastern food. And so on.
Gastronomic travelling - I agree with your strategy @Maggie8K, and I love the opportunity to support the local economy (well, my excuse for a pie & a pint!) whenever possible and discover new foods.
Yes! That’s one of the main motivators to travel 
I love exploring cafe’s, bakeries, pubs, supermarkets, markets. Definitely supporting the economy 
I am a local sitter and always bring my groceries and make simple meals. I’m not a huge take-out or eat out kinda girl anyway, so I’m usually making rice, mac&cheese, salads, nachos, soup, etc. And most of these are 1 pot meals, as like, you, I don’t love having to dirty a bunch of dishes either! But I definitely plan to eat at home, which is what I would do “at home” anyway
I usually do relativey short “vacation” sits, so there may be a fair amount of dining out, but because I’m staying someplace with a full kitchen, I take advantage and get food for breakfasts, lunches, as well soups and quality frozen entries for some dinners. There may be a little simple cooking as well. I’ve stayed in places with outdoor grills but haven’t been brave enough to try them! Last sit in San Fransisco we actually wound up dining “at home” twice using Ubereats to get great quality take out. We’d been out and about all day and just felt like chilling with the cats and watching movies on the humoungous television. During the summer we did a sit in Medford – part of the greater Boston area. We felt like going out one night but didn’t feel like going back to town and found an Italian place that felt authentically neighborhood. I also want to experience “local” delicacies, so a sit in Portland will definitately include some food truck fare (As a homeowner my welcome guide has a pretty extensive list of local restaurants and must eats!)
I usually bring a few grocery items so that I can cook. I also have cooked meals delivered a few times. There are lucky times when the owner tells us to cook some food in their fridge.
On my current sit I am mostly self catering but today I met up with friends (the sit is only 30 mins from home, in a gorgeous area) to ahem support the local economy - and very good it was too (we’ve already booked a return visit for when I do a repeat sit next month).
I bring all my cooking stuff with me in a collapsible box including pots pans water kettle, smoothie blender, spices, cooking oils, etc. then I just buy grocery and frozen berries. Most hosts will state to eat their food but I typically don’t because I like healthy food that I’m used to cooking.
I do the same, mainly because of allergies and also most of what has been left for me so far is really due for the bin. I have noticed that what I take is pretty much the same as when I take my touring caravan out for trips.