from Chef Jonathan Miller
This is a great casserole, not heavy at all, and deliciously perfumed with fennel and tarragon. If you find that it is not rich enough for you, try adding some feta cheese to it, either inside as a layer, or on top. Goat cheese would also be nice in it. This is also great with other fresh herbs that might be available: lemon thyme, parsley, marjoram, oregano are all nice, too. Experiment with different varieties of olives, or add capers, too. Lots of room for experimentation here. This is also a great party dish as it tastes great at room temperature and can sit out for a long time.
1 large or 2 medium fennel, halved, cored, and sliced crosswise
2 lb potatoes, sliced into 1/4" thick rounds
2 large red onions, sliced into thin rounds
4 tomatoes (from a can is great), diced
leaves from 12 branches thyme
1/2 t fennel seeds, coarsely ground
3 garlic cloves, peeled and sliced thinly
3/4 c green olives, pitted and roughly chopped
2 T chopped tarragon
Toss the fennel with a little olive oil and salt, then roast in a 400 degree oven until lightly colored, sweet, and softened, about 15-20 minutes.
Blanch the potatoes in salted, boiling water for no more than 2-3 minutes. You want them mostly cooked, certainly not mushy. For new potatoes, this time might be shortened somewhat.
Heat a large skillet and saute the onions in some olive oil over high heat until lightly browned and softened, about 8 minutes. Add the fennel seeds, some salt, and half the thyme and heat through another minute or so. Remove from the heat.
In a nice baking dish that is not too large, layer the gratin:
Drizzle a little olive oil on the bottom, then add half the onions and half the garlic.
Next, add the olives, half the remaining thyme leaves and half the tarragon.
Now layer the the potatoes, chopped tomatoes, and roasted fennel (in two or three layers, depending on how much you have), adding the remaining garlic as you go, here and there. Season the layers of potatoes with salt and pepper as you go, too.
Top with the remaining onions, a little more olive oil, and bake in the oven (still at 400), loosely covered about 20 minutes.
Uncover and finish the potatoes, perhaps another 15 minutes or so. When it is done, sprinkle any remaining thyme and tarragon leaves over the top. Serve warm or room temperature.