Ask HN: Side project for extra income question?

This is not a new idea, will never be a venture funded startup, and is unlikely to change the direction of my life - it's quite simple & straightforward and that's the beauty in it: create a better trail mix and sell it online. There are a number of uncertainties, mainly will the market accept my 'better' trail mix and if not manufactured at scale can I actually make money - those are to be determined though. My question to the community is: What is the cheapest way to have an MVP for a consumer packaged good like trail mix? Say 500 12oz units. I'm unable (I believe) to package in my garage due to food quality and control restrictions - so are there companies that would accept the empty bags with my design + raw ingredients and package the trail mix for me to then sell? Any advice/help would be appreciated. Thanks!