Rinse the pearl barley under cold water.
In a medium pot, combine the rinsed barley and vegetable broth, then bring to a boil.
While the barley cooks, prepare the mushrooms.
Melt the butter in a skillet over medium heat, then add the mushrooms.
Cook the mushrooms for about 5-7 minutes or until they're browned.
Add the halved cherry tomatoes and diced cucumber to the skillet.
Once the barley is cooked, drain any excess liquid and let it cool for a few minutes.
In a large bowl, combine the warm barley, sautéed mushroom mixture, chopped parsley, dill, red onion, and lemon juice.
Season with salt and pepper to taste, adjusting to your preference.
Serve immediately or refrigerate until ready to serve.
