Preheat oven to 400°F (200°C) to roast pears. In bowl, toss pears with apple cider, maple syrup, melted butter and lemon juice. Place in baking dish. Roast 25 to 30 min. until pears are tender and caramelized.
Meanwhile, in a large saucepan, heat cream, milk and sugar over medium heat, stirring occasionally, for 5 min. or until small bubbles start to form around the sides of the pan. Meanwhile, in a bowl, whisk egg yolks and salt. Gradually whisk half the hot cream mixture into yolks. Stir into mixture in saucepan. Cook on medium-low heat, stirring constantly with a wooden spoon or spatula, 10 to 12 min., or until sauce thickens and coats the back of a spoon. Whisk in bourbon and vanilla.
Immediately strain sauce through a sieve into a bowl. Set bowl in an ice water bath. Stir occasionally until sauce is completely cool. Press plastic wrap onto surface of cream sauce to prevent "skin" from forming.
Divide pear halves evenly among 8 plates and drizzle with pan juices and cream sauce.