I sometimes use Wayfarer foods, although not much now because its so much cheaper to take a bucket of rice or whatever. You can get them from lots of outdoor shops such as Blacks, I did some price comparisons a while ago and you can't get them online for much cheaper.
Where I got mine last: Typical meal £3.50 (+ postage so order in bulk)
www.foxsoutdoor.co.uk/camping/food/
That's cool, but two meals and a pudding will still set you back at least tenner + postage. Loooking at this, for eg.
http://www.shoponthefarside.co.uk/Ration_Packs_Ration_Pack_-_Menu_C.asp And you get the three retort packs plus all this:
Chicken Noodle, Crunchy granola bar, Cup a Soup Oxtail, Fruit Biscuits, Kendall Mint Cake Chocolate, Chewing Gum, Mixed Fruit, Isotonic drink, 4 x Tea Bags, 4 x Coffee, Creamer, Sugar, Hot Chocolate, Tomato Ketchup, Scouring Pad, Pocket Tissues, Antiseptic Wet Wipes
Obviously your £5 ration pack, if they can still be got, are better value still. I haven't tried for a while, I've still, just, got some stocks - including my last RCIR :-(
The best way to DIY on the cheap is tins, irish stew, all day breakfast etc, but when doing more than walking from the car park to the woods, there's a reason retort packs are popular - better fit in your pack, lighter waste and you can brew up / heat meal simultaneously.
Does anyone know any such good and cheap meals? Sainsburys do a "Long Life Bacon Brunch" which is very nice for brekky and filling @ £1.69. I've occasionally used "Look what I've found", but while nicer, it's not much cheaper than wayfarer, and the packaging means wasting brew water.