Cut 3 oz of brie cheese into thin slices. Make sure the cheese is at room temperature for easier spreading.
Evenly spread the slices of brie cheese on one slice of sourdough bread.
Spread 2 tablespoons of jam over the brie cheese.
Place the second slice of sourdough bread on top, pressing down gently to ensure the sandwich holds together.
Place 2 tablespoons of butter in a large skillet over medium heat.
Carefully place the sandwich in the hot skillet.
Cook the sandwich on medium-low heat for about 2-3 minutes, or until the bottom side is golden brown and crispy.
Carefully flip the sandwich with a spatula. Cook the other side for another 2-3 minutes, until it is also golden brown and the brie cheese is melted and gooey.
Once both sides are golden brown and the cheese is melted, remove the sandwich from the skillet.
Place it on a cutting board and let it cool for a minute to allow the cheese to set slightly.
Use a sharp knife to cut the sandwich in half. Serve immediately while the cheese is still warm and melty.