Preheat oven to 400°F. Wrap beets in foil and roast for 40-50 minutes until tender. Cool, peel, and slice.
Meanwhile, cook lentils with water and bay leaf in a saucepan for 20-25 minutes until tender but not mushy. Drain and cool.
In a small bowl, whisk together olive oil, red wine vinegar, Dijon mustard, minced garlic, salt, and pepper to make vinaigrette.
In a large bowl, combine cooled lentils, sliced beets, and thinly sliced red onion.
Drizzle vinaigrette over the mixture and toss gently to coat.
Top with crumbled goat cheese, fresh parsley, and chives before serving.