In a large skillet, heat 2 tablespoons of olive oil over medium heat. Add diced red bell pepper, green beans, and red onion. Sauté for 7-9 minutes until tender. Season with salt and pepper, then transfer to a bowl to cool slightly.

In a small bowl, whisk together ¼ cup of olive oil, lemon juice, Dijon mustard, ground cumin, salt, and pepper. Add freshly chopped dill to create the dressing.

In a large bowl, combine rinsed lentils, sautéed vegetables, and half of the crumbled feta. Pour dressing over and toss gently until well-coated.

Garnish with remaining feta and fresh dill before serving warm, chilled, or at room temperature.