Bon Appetit !
Cover the entire dish with sliced potatoes and brush with olive oil. Place the dish in a medium to high oven and bake until the potatoes are cooked. Then the whole dish will be cooked. Brush the potatoes with a little melted butter and pass the dish under the grill or broiler and finish to a nice golden brown if needed.
Add some raw spinach at this point if you have some. You can also use kale but don't use cabbage. It won't be cooked and it will dominate the taste of everything else.
Saute off a little chopped onion and garlic and add the vegetables when the onions are a little translucent. Add some vegetables stock or water. In this case vegetable stock is better but if you don't have any don't let it put you off. Bring a to boil, lower heat and cook for a few minutes. At this point you need to correct the seasoning and add any herbs you like. I added oregano to this but you can use thyme too. Put the entire mix into a Pyrex or any oven worthy dish and flatten the vegetables by cutting the big ones if neccesary. If not you won't get a level layer of potato.
Prepare a variety of vegetables by peeling, washing and blanching them. The reason for blanching is that the vegetables retain their color better and you can slightly precook the most hardy ones like the carrots so that everything will be cooked at the same time. Use a good variety of vegetables. Here I used cauliflower, butternut squash, white turnips, whole baby parsnips, zucchini, carrots, brussels sprouts, and large raw mushrooms plus a whole peeled fresh tomato.
Hard to believe I ate all this.