In a small-medium saucepan, bring the lentils and water to a boil. Cover, reduce heat to low, and simmer 40 minutes, or until the lentils are tender and water is absorbed.
Preheat a medium skillet with 2 Tbs. extra virgin olive oil over medium heat. Add the onion and leek and a pinch of salt. Continue to cook for 3-5 minutes, until lightly caramelized.
Hollow out the center of the pan by pushing the leeks and onions to the sides. Add the radishes right in the center so they have direct contact with the hot pan. Cook 3-5 minutes, or until the radishes are lightly caramelized. Add the kale to the pan, and cook until tender, about 2-5 minutes. Stir to combine all of the veggies.
In a large serving bowl, combine the cooked lentils and vegetables, and drizzle with remaining olive oil, vinegar, garlic, sea salt and black pepper. Garnish with cheese, if using, and gently toss to evenly coat ingredients with dressing. Can be served warm or cold. Leftovers can be stored in an air-tight container for up to 3 days.