Toast rinsed barley in a dry skillet for 1 to 2 minutes, making sure the barley doesn't stick to the pan. Transfer to a medium pot and add broth and water. Bring to a boil; cover and lower to simmer for about 40 minutes, until barley is tender but not mushy. Turn off heat and keep covered for another 5 to 10 minutes until all the moisture is absorbed. (If there is any liquid left, strain barley and return to pot.)
I sautéed the onions in two batches so they would cook faster.
This recipe makes a lot as I like to freeze the leftovers. You can easily cut the recipe in half for fewer people.