Mix flour, baking soda and salt; set aside. Microwave chocolate and butter in large microwaveable bowl on HIGH 2 min.; stir until chocolate is completely melted. Whisk in cream cheese. Add 1 cup sugar, egg and vanilla; mix well. Stir in flour mixture. Refrigerate 15 min.
Roll dough into 1-inch balls; coat with remaining sugar. Place, 2 inches apart, on baking sheets. Press your thumb into center of each ball; fill each indentation with about 1/4 tsp. jam.
Bake 8 to 10 min. or until lightly browned. Cool 1 min. on baking sheet; transfer to wire racks. Cool completely.