You need to find a co-packer to manufacture for you. You`re not necessary "selling" them your recipe, but rather, hiring / contracting them to produce for you. That way, you`re a customer to them, and more likely to get their attention.
Can you think of a product that is very similar, that will just require some different ingredients? It`s going to be hard to find a manufacturer to add equipment to manufacture a new concept for you, so you need to think creatively about how the production process could be done. For example, if this were a pocket sandwich with s`more filling, you could approach pizza pocket mfr`s.
You will also need a packaging designer and printer to make your boxes/labels and ship them to your co-packer.
If you describe the product for us here, maybe we can help think of some production ideas.