Preheat oven to 350°. Toss together first 3 ingredients. Place peaches, cut sides down, on a parchment paper-lined jelly-roll pan. Bake 25 minutes or until juices begin to caramelize, turning after 15 minutes.
Transfer peaches and juices to a food processor; cool completely (about 30 minutes). Add orange juice, cinnamon, and salt; process until smooth. Stir in lemon juice. Cover and chill 4 hours.
Combine crème fraîche and vanilla bean paste. Ladle soup into bowls; dollop with crème fraîche mixture.