Ask HN: Advice for food startups?

These days it seems most of the large food corporations prefer to expand their portfolios / fund their R&D by acquiring medium sized food brands. This makes food entrepreneurship in the food space rather appealing since it shouldn't require much, if any, VC money and seems to have a rather generous payout; plus, it seems a lot less crowded with less risk than opening a restaurant.

Suppose you already have an idea and general process worked out for a food product. How do you go from making that product in your kitchen to putting it on store shelves? How do you determine you have product-market fit for more than a niche segment of consumers? Any tips or general advice?