• Preheat the oven to 350°F. Line a baking sheet with parchment paper.

Bake the bread

• Brush olive oil evenly over the baguette slices. You may need more than 2 tablespoons but be sure not to totally soak the slices; you just want to brush an even layer on top of one side.
• Place the baguette slices onto the prepared baking sheet and bake for 10 minutes, flipping bread slices over halfway through the cooking time.

Caramelize the onions

• In a large non-stick skillet or cast iron skillet, heat 1 Tablespoon olive oil and the butter over medium-high heat.
• Sauté onions, stirring regularly, for about 5 minutes.
• Reduce heat to medium, sprinkle in brown sugar and stir together. Continue cooking, stirring every once in a while, until caramelized, about 9-11 more minutes.

Make the cheese spread

• In a medium bowl, combine the goat cheese,thyme, salt, and pepper with a fork or whisk until well combined. Set aside.

Cook the mushrooms

• In a separate cast iron skillet or nonstick skillet, heat 1 Tablespoon olive oil over medium-high heat.
• Once the oil is hot, add the mushrooms. Stir and sauté mushrooms for 2-3 minutes, until soft.
• Add the garlic and stir, sautéing for just about 30 seconds to 1 minute, just until the garlic is soft and fragrant.
• Add the balsamic vinegar, salt, and pepper, stir to combine, then turn off the heat.

Assemble the crostini

• Spread goat cheese spread mixture evenly over each crostini.
• Top with about ½ tablespoon to 1 tablespoon of caramelized onions
• Top with mushrooms.
• Sprinkle chopped thyme to garnish.