(2-part post):
Meal 1:
Buy some 'value' mince from a Asda, Tesco, etc. Divide it into 100g portions. (That typically works out at about 24p per portion).
Also buy some 'value' pasta sauce (or Asda's cheap Bolognese sauce). That's about 36p per jar. You're going to use ½ jar at a time, so about 18p per portion.
Brown a portion of mince in a frying pan (with a very small amount of oil). Add the pasta sauce. Cook for about 20 minutes, stirring occasionally. In the meantime, cook some 'value' pasta. (You get 6 or 7 portions from a pack costing about 40p, so say 7p per portion). Then simply pour the mince and sauce over the pasta. So you've got a meal for about 50p. (Adding some 'value' mixed herbs and/or some black pepper will enhance it, but it's not strictly necessary).
Meal 2:
As above (using up the other half of the jar of sauce) but add some chilli powder to the sauce and cook rice instead of pasta. So you've got an equally cheap chilli con carne. (OK, it's not got the beans which you normally associate with chilli con carne but it still tastes good).