Servings: Serves 8
Preheat oven to 350° with 2 racks centered. Cover and bring a large saucepan of water to a boil over high heat. Slice each vegetable crosswise very thinly. Working in batches, transfer vegetables to boiling water to cook, just until softened but not falling apart, 2 to 3 minutes. Using a slotted spoon, transfer vegetables to a colander, and place under cold running water. Shake colander well and transfer blanched vegetables to a baking sheet or piece of waxed paper. Continue until all vegetables are blanched. Set aside to cool.
To make béchamel sauce: In a medium skillet melt butter over medium-low heat. Sprinkle flour over butter and whisk until flour is cooked and well combined, about 2 minutes. Whisking, pour in the hot milk. Continue to whisk until sauce is well combined and thickened, 3 to 4 minutes. Whisk in cheddar, thyme, salt and pepper, until cheese melts. Remove sauce from heat.
Butter sides and bottom of a 6-inch spring form pan. Layer vegetables in concentric circles covering bottom of the pan. Every 2 to 3 layers, press firmly with fingers to even out layers. (Vegetable rounds do not have to be perfectly overlapping or spaced.) Spread 3 to 4 Tbsp. béchamel over vegetables, salt and pepper as desired. Continue layering and spreading sauce until vegetables are a few layers over rim of pan. Sprinkle remaining grated cheese over top. (Completed gratin may be covered with plastic wrap at this stage and refrigerated up to 4 hours. Remove plastic wrap before continuing.)
To cook: Cover with foil and place on a baking sheet (to catch spills) in oven. Cook until heated through and vegetables are tender, 30 to 45 minutes; remove foil for last 15 minutes.
While gratin is cooking combine breadcrumbs, melted butter and thyme in a medium bowl. Arrange breadcrumbs in an even layer on a baking sheet. Toast in oven until golden, about 5 minutes. Set aside to use as garnish on gratin sides.
To serve: Let sit at room temperature about 5 minutes. Run a knife around inside of gratin. Open pan, remove sides, and using a large spatula, transfer to a serving platter. Press breadcrumb mixture around sides of gratin. Arrange thyme sprigs. Cut into wedges to serve.
Adapted from Back to the Table by Art Smith
From the December 2002 issue of O, The Oprah Magazine
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