This may sound a little odd at first, but it's very easy and frugal. I just throw whatever leftover veggies and beans I have in a freezer bag for a couple of weeks, like corn, carrots, potatoes, beans, onions, peppers, just everything and when I have enough or feel like having soup, I throw it in a pot with some low sodium chicken broth and any leftover meat if I feel like meat and either rice or pasta, depending on what I feel like. Cook it all up, doesn't take long since the veggies and stuff are already cooked. Season to taste, also depending on what you feel like, you can add soy sauce if you want something asian, or curry if you want something spicy, italian season is great especially if you add a can of chopped tomatoes, it makes it like a minestrone soup.