Prepare a gas or charcoal grill. Meanwhile, slice the bread to ¾-inch and brush each side with the olive oil.
Toss the mushrooms in a enough of the olive oil to lightly coat and season with a pinch of salt.
Grill the mushrooms directly on the grate or in a grill basket, turning or stirring once, about 5 minutes. Meanwhile, grill the bread slices to mark both sides.
Roughly chop the grilled mushrooms and place the grilled bread in a 200 degree oven to keep warm.
In 1 teaspoon olive oil, saute the shallots and garlic on medium-low heat until fragrant and translucent.
Add thyme leaves and vinegar.
Pour the shallot-vinegar mixture over the mushrooms and mix well with the remainder of the olive oil/ Season to taste with the salt.
Serve with warm bread and Roasted Garlic-Tarragon Cream Cheese.
In a small sauté pan, caramelize the garlic in oil over very low heat for approximately 20 minutes, stirring often to prevent scorching.
Drain garlic and reserve the garlic-flavored oil. Set aside to cool.
Mix cream cheese with cream, chopped tarragon, roasted garlic, onion powder, black pepper, and salt in a food processor until ingredients are completely combined.
Move mixture to a small dipping bowl and garnish with whole tarragon leaves and a drizzle of the garlic-flavored oil.
Serve with grilled mushrooms and toasted bread.