It worked. I'm saying no more but, oh, the relief! :-)
What else worked was what I did with the tuna/cottage cheese.
I had about 120g of drained tuna (flakes, not chunks or steaks) and I topped that up to 200g with 0% cottage cheese and mixed it together. I then added a bit of salt and pepper, about 10 mls of balti curry paste (allowed) and 10g of mango chutney (not really allowed but tough and from Aldi so not dreadfully costly). A shake of lemon juice and I mixed it all together and had it with salad veg. It was filling but the tuna was much nicer, not dry and it was flavoursome. I shall do that again.
B: muesli, natural yogurt and a bit of stevia
L: chicken and chickpea soup (recipe here)
D: sardine temptation (adapted from something on a River Cottage programme), broccoli, fruit yogurt
From the freezer
The chicken, stock and chickpeas for the soup
Bit of cheese for the sardine dish
The frugal factor
The muesli was a gift
The chicken is leftovers with stock from a boiled up carcass. I'm nearly out now and it's proven so useful, I might buy a chicken, roast it and freeze the lot in portions to replenish my supplies.
Sardines in cans are not expensive.