Cook lentils according to package (we boiled covered for 20 minutes), drain, and set aside.
Meanwhile in a large pot boil your chopped potatoes and sweet potatoes until they are tender (~30 minutes). When they're finished drain them into a large bowl, and mash them together with 2 heaping spoonfuls of non-dairy butter/margarine. Season to taste with sea salt and freshly ground pepper. While potatoes are cooking, heat oil in a separate large pot or tall pan.
On medium heat cook onion, carrots, jalapeno, celery, and garlic powder. Stir often for about 5 minutes until vegetables soften.
Add mushrooms, 2 bay leaves, 1/2 tsp dried sage, 1/2 tsp dried tarragon, 1/4 tsp dried thyme. Stir often for 4-5 minutes.
Stir in 1/4 cup tomato paste, 1 cup vegetable stock, and tomatoes with their juice. Boil and simmer for about 20 minutes, stirring occasionally.
Heat oven to 400 degrees.
Stir in green beans and lentils with the rest of the vegetable mixture. Cook for about 3 minutes.
Spread the vegetable mixture evenly into a large glass baking dish.
Spoon the mashed potato mixture over top of the vegetable mixture. Spread it around evenly, then bake it uncovered for 30 minutes. Let it rest for at least 5 minutes after you take it out of the oven. Have a satisfying meal! :)