How should you cook farro? Rye berries? Basmati rice? Brown rice? Wild rice? Barley? What precise proportion of liquid:grain and time is needed? Here's a secret I learned from my chef sister-in-law: It really doesn't matter (?!)
Here's what you do, regardless of the grain: Put in more water than you'll need. 2:1 water to grain is almost always enough, but no harm in going with 3:1 to be safe. Add a few shakes of salt. Bring to a boil, then reduce to a simmer, and cover (or don't, but then err on the side of more liquid).
And then you...test every so often. If it's a hardy grain, maybe take your first look after 15-20. If it's softer/quicker to cook, check after 5-10. And then just keep tasting every few minutes, and eventually it'll be done. You can then take your pot to the sink along with a strainer, drain the grains, then leave the draining grains, in the strainer, resting on the pot, while you finish whatever else needs to be finished for your meal.
If you want to get fancy, you could put the grains back into the now-dry pot with a bit of cider (or other) vinegar to add a bit more flavor while everything's finished. But that's really all there is to it.
Pretty neat, huh?
The picture at the top is a farro bowl I made out of Geechie Boy Mill's farro piccolo, using this technique. It really is shockingly versatile. There may well be times where you want to cook your grains another way, and that's great and often quite worthwhile, but hopefully this can help reduce the intimidation factor with other grains you might encounter (either at the store, or in a future essentials box -- look out for some rye berries!).