Is this for you at all

It is an acidified food

A sauce made from vegetables, aromatics and acid is the thing 21 CFR 114 was written about. That is not a technicality: it means a scheduled process established by a process authority, a filed one, and records showing you hit it on every batch. The paperwork is the business, and the recipe is what you make once the paperwork exists.

This is where the comparison to jam is worth making, because people make both in the same kitchen and assume the same rules. Jams, jellies and preserves are named in the exclusion list of the acidified foods definition. A sauce is not. Same stove, different regime.

It is thick, which makes the process harder

Heat moves through a thick sauce by conduction rather than convection, so the middle of the jar lags the edge by a long way. A process that is plenty for a thin liquid can leave the center of a thick one short, and you cannot tell by looking. Viscosity is the reason a sauce needs its process established rather than borrowed, and it is the single most common thing a new maker does not know.

It is sold in glass, and glass is heavy

A case of filled 16 oz jars is dense, and freight on a heavy, breakable product is a real line in the price rather than something the customer sorts out. Makers who sell at a market discover this on their first mail order, usually while quoting it to somebody who then does not buy.

What makes it a good business anyway

The same things. A filed process is work done once per formulation and amortized across every jar you ever make of it. A thick sauce has a long shelf life and does not need a cold chain. And glass is what the category expects, so the packaging decision is largely made for you.

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