01 - Preheat oven to 425°F. Line a baking sheet with parchment paper.
02 - Toss the sliced bell peppers with olive oil, kosher salt, and black pepper. Spread in an even layer on the prepared baking sheet. Roast for 20–25 minutes, turning once halfway through, until the peppers are tender and the edges are lightly charred. Remove from the oven and let cool slightly.
03 - While the peppers roast, rinse the farro under cold running water. Combine the rinsed farro, water, and kosher salt in a medium saucepan. Bring to a rolling boil over high heat, then reduce to a simmer. Cook uncovered for 25–30 minutes until the grains are tender but still retain a pleasant chew. Drain any remaining liquid and set aside to cool.
04 - In a small bowl, whisk together the extra-virgin olive oil, fresh lemon juice, dried oregano, minced garlic, Dijon mustard, sea salt, and black pepper until the mixture is fully emulsified and creamy.
05 - In a large mixing bowl, combine the cooled farro, roasted peppers, cherry tomatoes, diced cucumber, sliced red onion, Kalamata olives, and chopped parsley. Pour the dressing over the mixture and toss gently until everything is evenly coated.
06 - Divide the dressed grain bowl mixture among four serving bowls. Sprinkle crumbled feta cheese generously over each portion. Serve at room temperature or chilled.