This is a good dish to use up those radish greens. If you use a large-enough oven-proof skillet, you can just cover that and pop it in the oven rather than using a baking dish.
2 bunches greens
2 large onions, sliced
1 garlic clove, minced
6 T butter or oil, divided
1-1/2 c broth
salt and pepper, to taste
1-1/2 lbs potatoes, (peeled), thinly sliced
1. Preheat oven to 375ºF. Bring a large pot of water to the boil.
2. Trim and wash greens, separating tough stems from leaves, if necessary. Chop coarsely. When water is boiling, add greens, pushing them down into the water. Cover. When the water returns to the boil lift greens out with tongs or a slotted spoon into a colander or drain directly into a colander. Press out as much water as possible.
3. In a large sauté pan, heat 4 T of the butter or oil over medium heat. Add onions and garlic and sauté until they are softened and just beginning to brown, about 10 minutes. Add the broth and bring to boil. Remove from heat. Season with salt and pepper.
4. Add potato slices and greens to the onion mixture and stir to combine. Transfer to a baking dish, pressing down firmly. Dot the vegetables with the remaining butter or drizzle with remaining oil. Cover the dish tightly with foil and bake 45 minutes. Remove the foil and bake 15 minutes more, or until the potatoes are very tender.
Note: The baking time can vary, depending on the thickness of the potato slices. Check after 30 minutes; if the potatoes seem almost done, then uncover and cook for 15 minutes longer.