To add to this, basic sliced bread, milk, mixed size eggs, baking supplies, peanut butter, beans, soup, ketchup, frozen veg, brown sauce etc, some veg and salad all really well priced and good reductions sometimes available although I've not found anything the last couple of times I've looked.
Sausages, bacon and big packs of chicken also good quality and not badly priced.
We also get the £12 gastro pub dine in as an alternative to a takeaway. I like the fish and chips or the paella, then you can get a side and dessert. The twin pots of panna cotta are lovely.
I also want to try the laundry liquid after seeing it recommended on here as an alternative to Persil non bio which has been changed to become really strongly fragranced but we have a big Costco bottle to get through first.
We have one in walking distance so go there quite often.