My favourite recipe book 101 cheap eats bbc good food. You can google many of the recipes.
Meat
Chicken thighs or whole chicken, avoid chicken breast overpriced,
pork shoulder steaks
Braising beef - cook slowly with carrots and onions in beef stock, serve with potato. Perfect.
Make stock by gently boiling the chicken carcas for 1to2 hrs, use this to make risotto with leftover chicken, rice, onion, sweet corn, garlic.
Veg
carrot
onion
cabbage stir fry
Swede
etc.
Coleslaw home made, grated cabbage, carrot, celery as a base with salad cream. Add a few grapes or raisins for interest.
Cereal
Stick to porridge - all the rest are mainly very expensive air and sugar and wont fill you up. Add chocolate spread or nutella as previous poster said if needed. Otherwise add fruit banana or sultanas for sweetness.
Eggs - omlette, fried, Etc,,eggy bread make one egg go further.
E.g. make pancakes, kids love makemaking them and they are filling, specially if Served with grated cheese and or bacon/ham as in a French creperie. Or make thick american pancakes/dropscones with some raisins in for sweetness/fibre.
bbc sausage and bean bake - see google - makes a packet of good sausages go further.
Soup - use stock as above, chuck in chopped veg and lentil, or chick peas, add a few chilli flakes. lots of recipes on www.
Pasta makes the plate look full but not that healthy I dont use it much, rather eat smaller portions of more nutritious stuff. Its empty calories. Unless you are going to use the calories, e.g. energetic or rapidly growing teenager.
Chilli, fry 500g mince, add tin of chilli beans, tin of tomato, heat and serve with rice.