Directions

1. Preheat oven to 400 degrees. Break off 2 cloves garlic; finely chop and reserve. Trim tip off each garlic head, exposing tops of cloves. Place heads on foil, drizzle with 1 teaspoon olive oil, and season with 1/4 teaspoon salt and 1 teaspoon thyme. Wrap tightly in foil. Roast until garlic is soft, about 45 minutes. Squeeze cooked garlic from cloves and discard skins.
2. Mix chopped garlic with lemon zest, parsley, and a pinch of salt and pepper; set aside. Place the shiitakes on a baking sheet and toss with 2 tablespoons olive oil, 1/4 teaspoon salt, and remaining thyme; roast until sizzling and tender, about 12 minutes. Sprinkle with garlic, parsley, and lemon mixture.
3. Heat a grill pan over medium-high heat and toast bread on both sides until golden brown. Spread roasted garlic on one side of each piece of toast and top with 3 mushroom caps. Serve warm.