Start this recipe by cooking the potatoes in a pan of boiling water until soft. Meanwhile, season the flour with salt and pepper and roll in the mushrooms, carrots and zucchini to coat. Heat the margarine in a large pan and cook the vegetables for 3-4 minutes. Add in the tomato paste, herbs and ½ cup vegetable stock and stir. Add in the frozen peas and cook for 3-4 minutes before adding in the cooked tinned lentils and sweet corn. When the potatoes are cooked through, drain and mash with the cream cheese, an extra knob of margarine and season well with salt and pepper. Spoon the vegetables in an oven proof baking dish and carefully top with the mash potatoes. Sprinkle over the Parmesan cheese and bake in a hot oven at 200`c for 15-20 minutes or until golden brown.