In saucepan, add lentils and vegetable broth. Bring to boil, reduce heat to low simmer, covered until lentils are al dente. Do not overcook. Drain any excess liquid, and spread out on a baking tray to cool.
Meanwhile in a large pan, add 1 tbsp oil and onions. Add salt and garlic powder, and cook until onions are translucent, stirring often. Add the 1 tbsp balsamic vinegar, and cook another 5 minutes until onions are browned, adding bit of vegetable broth if getting too dry.
In separate skillet, cook carrots in a bit of oil for 2-4 minutes until just crisp-tender. Add cabbage to the pan, sprinkle with salt, garlic powder, oregano and parsley, and cover. After 3 minutes, stir, and cook another 5 minutes. When cabbage is crisp-tender and slightly browned, remove from heat.
In a mixing bowl, whisk dressing ingredients together. Add the cabbage, carrots, olives, along with the cooked lentils. Stir gently.
Just prior to serving, squeeze lemon juice over top of the salad.