Preheat your oven to 375°F. Slice the French baguette into 1/2-inch rounds and arrange on a baking sheet. Brush each slice lightly with olive oil.

Slice the Brie cheese into thin pieces, about 1/4-inch thick.

Scoop out about 1 cup of fig jam into a small bowl. Optionally mix in some chopped fresh rosemary.

Spread a generous layer of fig jam on each toasted baguette slice. Place a slice of Brie cheese on top, then sprinkle with chopped walnuts and fresh rosemary. Season with salt and pepper.

Bake the assembled crostini for an additional 5-7 minutes until the Brie is melted and bubbly. Let cool slightly before serving.