My girlfriend and I cook 99% of our meals from scratch — our weekly shopping bill (not just food, but everything) averages out at about £50 (including wine).
We buy a lot of Tesco Value/Asda smart price goods and apart from one or two things, there really isn't any point in buying the branded stuff.
We also get a really varied, balanced diet. My average day would consist of the following:
Breakfast
50g of Tesco Value Oats
1 Tesco Value Banana (Chopped)
1 pot of Tesco yoghurt
Lunch
Always a salad with a variety of ingredients:
Asda smart price Feta or Mozzarella
A couple of olives (Tesco discount brand)
1 tomato
Some sliced cucumber
Some sliced Tesco value pepper
Asda smart price pesto (red or green)
Splash of balsamic vinegar
splash of olive oil
salt and pepper
Apple or orange for desert.
Dinner
We have a good selection of evening meals that we rotate but the cheapest meals that go a long way are bolognese or chilli because we get the big packs of Tesco Value mince and make 5-6 portions, freezing what we don't eat.
Tomato soup can be made quickly and easily:
Slice 1 Tesco value red onion and fry in a pan
Add 1 Tin of Tesco value chopped tomatoes
chuck in salt/pepper/dash of wine to taste
Add a couple of spoonfuls of Tesco value soft cheese
If you want a smooth soup, blend it before serving.
Another thing we do quite often is make a roast on a sunday and then use any meat we don't eat throughout the rest of the week. A whole roast chicken can make three evening meals as well as providing plenty of meat to go into the salads above.
Changing to value/smart price produce was probably the best thing we ever did.
There's absolutely nothing wrong with the food and you get a lot more for less.
Rice, pasta, potatoes, tinned veg, fresh veg — you can't really go wrong. If they don't do a Value version of the product, they usually do a 'discount brand' version which is much cheaper than the named-brand product.
We've had a lot of fun trying Value versions of things we used to insist had to be named-brand. Nutella, Marmite, honey, crisps etc.
Something else we noticed is, quite often the Value stuff tastes better than the standard Tesco branded equivalent.
The only named-brand item we can't ween ourselves off is Diet Coke!