10 large shallots, peeled and halved
1 cup garlic cloves (about 20), peeled
4 large leeks, white and pale green parts only, split and cut into 1'' pieces
2 cups pearl onions, peeled
2 cups cream
kosher salt and freshly ground pepper to taste
4 sprigs fresh thyme
1/4 cup grated parmesan cheese, optional
1Place the shallot halves and leek pieces, cut side down, in a 2 quart baking or gratinée dish (about 9x13). Scatter over the garlic cloves and pearl onions.
2Pour over the cream and season well with the salt and pepper. Lay the thyme sprigs over the top and then cover with heavy plastic wrap and then aluminum foil.
3Bake at 350 degrees for 1 to 1 1/2 hours, or until the vegetables are very tender and pierce easily with a fork. Remove from the oven and unwrap.
4The dish can be prepared up to two days ahead to this point. Sprinkle the onions with the parmesan or simply return to a 400 degree oven to brown lightly and heat through, about 10-15 minutes.
If you don't get around to this for Thanksgiving, it is delicious served with prime rib, roast lamb or even a whole roasted salmon (think Christmas dinner!)