Mince the onion, and dice the tomato.
Melt the butter or olive oil in a medium-sized saucepan with a lid over medium-high heat. Add the onion and salt and cook until the onion begins to soften and brown around the edges, 4-5 minutes. Add the spice blend and tomato and cook 1-2 minutes.
Add the water and bring to a boil. Add the barley and evenly spread around the pan. Cover, reduce the heat to low, and cook until the barley is tender and the liquid is absorbed. After 15 minutes, taste a grain, if it's not tender but there's no more liquid in the pot, sprinkle 2 Tablespoons more water over the top, cover, and continue to cook.
Once tender, remove the barley from the heat. Set aside for10 minutes, keeping the lid on. Fluff with a fork and serve hot.