Combine Boursin cheese and softened cream cheese in a mixing bowl using an electric mixer on medium speed until smooth and creamy.

Scoop the cheese mixture into a brain-shaped mold, pressing it down gently to remove air pockets. Cover with plastic wrap and refrigerate for at least 4 hours or overnight.

Remove the mold from the refrigerator, take off the plastic wrap, and gently invert the mold onto a serving platter.

Mix red pepper jelly with a tablespoon of warm water until it reaches drizzling consistency, then pour it over the dip.

Serve the creepy brain dip with crackers, veggie sticks, or toasted bread, allowing it to sit at room temperature for 10 minutes before serving.