I've thought about this a lot as it's effectively my idea of Origin Marks (not the same as the curvy OM/GI system), that are like trade marks but they serve the consumer rather than the companies.
Anyway, all companies have lists of what they buy and who from in their accounts - and their banks and suppliers can corroborate those details.
I think I'd provide limits for micro-businesses (1-2 employees, below the VAT threshold in UK), and maybe have limited reporting for SMEs too. Only listing all suppliers, say.
But for larger businesses, they should list the goods/services they use and the origin of all inputs to a product (including energy). Down to the factory, not a trade mark, the actual inputs.
Companies already keep all this information.
Capitalism supposedly optimises markets, but it can't do anything like that without full information. I mean the psychological manipulation of 'brand marketing' also opposes the supposed optimisations of capitalism too, but that's another story.
All this information is already maintained, it's just not exposed for the public.
What farm was my chicken produced on? Then I can look at that farm to see if they bought a tonne of penicillin, or a GM feed. I can look at the farm to see if they have outside access for the birds, say.
We can also readily graph essential businesses for food security, and new companies can easily find suppliers, B2B companies can find gaps and opportunities - the whole web of production can be mapped this way.
You can also spot corruption and loss. Consumers can avoid companies that use upstream suppliers they disprove of - like if a footwear company has a factory in an area known for human rights abuses, that's now public info, I can check it out if I want.
Anyway, restaurants already have to know the origin of their goods for pubic health purposes, codifying can just mean the suppliers send them an enhanced receipt that the restaurant catenates with others and uploads to the government, that can be done as part of the same process as finance reporting.
If you're buying chicken out the back of a van in an alley then you're going to have extra work; if you're just using standard supply chains it should all work pretty seamlessly.