I don't know if this is the type of thing you were asking, but it's one I've been using about once a week lately.
I was listening to How I Built This with Guy Raz, and he had on a lady that wanted to eliminate food waste. She started the app Too Good To Go.
Partner businesses will pack up about $15 of food at the end of the shift, and instead of tossing it, they put it in a to go box for you for $5.
Tonight we had jerk chicken and sides from a Caribbean place, another time we got 4 big pizza slices overloaded with toppings, and our favorite is the Manhattan Bagels gives us 15-17 bagels. We've also tried a vegan bakery, which is way too expensive for us, but for my girlfriend's nephew with a severe egg allergy was a great surprise.
These are all places we wouldn't normally go, but they've all been really tasty, helped eliminate some waste, and let us try some new restaurants for a fiver. We're kinda in the country, so there aren't too many options, but I looked in the nearby city and there are a lot, and the app started in Europe, so you non-US people don't have to miss out.
So maybe not the super cheap lentil curry recipe I have, but this was an intriguing things I recently learned about and have been looking to share awareness about.
Even if you don't have much cash, it still feels nice to be able to get restaurant food sometimes too, and this is a cheap and mutually beneficial way to do that.