Mushroom Bruschetta

Place the oven rack in center position.

Heat the oven to 400 degrees F.

Place the mushrooms in a medium-sized bowl, drizzle in olive oil, season with salt and pepper. Toss to coat.

Spread the mushrooms out on a parchment-lined rimmed baking sheet in as close to a single layer as possible. Roast in the oven until slightly browned, about 12 minutes. Set aside. Prepare the sauce: Meanwhile, in a large saucepan, melt the butter over moderate heat. Stir in the flour until a paste forms. Gradually pour in the ¼ cup milk, whisking until smooth. Bring the béchamel sauce to a simmer over moderately high heat, whisking constantly, until thickened, about 4 minutes.

Add the remaining 3/4 cup milk. Reduce the heat to low and cook, whisking often, about 10 minutes.

Remove from the heat and stir in the taleggio and fontina cheese until melted, followed by the thyme leaves. Season the sauce with salt and pepper.

Add the roasted mushrooms and all their juices to the pan, stirring to re-heat.

Remove from heat and pour into a serving bowl.

Serve warm as topping for the toasted baguette slices.