Thank you for your response.
But I don't think that bundle will be ideal as I cannot provide sales price for each item in the bundle. For example, if I have a beetroot salad with walnuts I sell the whole salad £4 and I don't have separate prices for beetroots, olive oil, salt etc that I have used to create my final product.
I think that I will use non-stock items for those I sell, and either stock (so I can track my inventory) or non-stock (I will post an adj. journal every month after the stock count) for purchases.
Do you think that this is a good idea?