Ingredients would be:
- water (1,000g)
- barley / wheat / rye (1,000g)
- sugar (100g)
Tool would have to be a vat/pot of some kind and would require a heat source.
I'd suggest a two-step production process. Mixing and heating the ingredients produces 2,000g of "Wort". In real life this only takes about an hour - so this could be an IG effort of half a day - one day.
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The second process would be to Ferment it
Tool required would be a fermenter
Materials: Wort
In real life it takes about 2 weeks for the beer to ferment. So maybe a couple of days fermenting would be appropriate.
End result is beer, each serving could be 100g as normal food - or you could make it a healing food just for kicks

Having a fermentor could also lead to the production of wine. Ingredients for wine would be grapes, water and sugar. Production time should be a few days minimum given that wine takes months to produce.