Preheat and Prep Vegetables - Preheat your oven to 400°F. While the oven heats up, chop the bell peppers, zucchini, sweeet potatoes, carrots and red onion into bite-sized pieces. Halve the cherry tomatoes.
Roast the Vegetables - In a large bowl, toss the chopped vegetables with olive oil, salt, and pepper. Spread them in a single layer on a baking sheet and roast for 20-25 minutes, or until tender and slightly caramelized. (I like to group my veggies by density, the softer ones that cook faster on one tray and the harder ones (sweet potato, carrot) on another one so I can adjust by doneness.
Cook the Lentils - While the vegetables are roasting, cook the lentils according to package directions. Usually, this means simmering them in water or broth for about 20-25 minutes until tender. Drain any excess liquid.
Prepare the Dressing - In blender, blend together olive oil, balsamic vinegar, Dijon mustard, shallot, garlic, salt, and pepper. Adjust the ratios to your taste preference with honey or maple syrup.
Combine - In a large bowl, combine the roasted vegetables, cooked lentils, chopped cucumber, lightly chopped greens, feta and fresh herbs. Pour the dressing over the salad and toss gently to combine.
Serve and Enjoy - Taste the salad and adjust seasonings as needed. Serve the Roasted Vegetable Lentil Salad warm, cold, or at room temperature. It’s perfect as a light lunch or a side dish.