Preheat oven to 400 degrees F.
Place garlic in a baking dish just large enough to hold the garlic in a single layer. Drizzle with oil, and season with salt and pepper. Roast, uncovered, until the garlic is soft, about 1 hour.
To serve, squeeze garlic cloves from each head, and spread on bread. Top with cheese, and serve.
To store, squeeze garlic cloves into a small jar. Add thyme and lemon juice. Pour enough oil into jar to cover garlic. Cover, and store refrigerated for up to 10 days.
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