Combine sugar, water, and syrup in a small Dutch oven, stirring well; cook over medium heat, stirring constantly, until sugar dissolves and mixture comes to a boil. Cover and boil 2 to 3 minutes to wash down sugar crystals from sides of pan; uncover and continue cooking, without stirring, until mixture reaches soft ball stage (238°).
Pour syrup onto a marble slab that has been sprinkled with ice water; cool to lukewarm (110°). Using a candy scraper or wooden spoon, flip edges of syrup into center mass until fondant is opaque and creamy. Add vanilla, and knead, with buttered hands, until mixture is smooth. Make a well in top of fondant; pour one-fourth of melted chocolate in well. Knead until well blended. Repeat procedure with remaining melted chocolate. Shape fondant into a ball, and store in an airtight container overnight.
Melt fondant in top of a double boiler over simmering water, stirring constantly. Pour into miniature aluminum candy liners; let stand until hardened.
Place dipping chocolate in a stoneware bowl that has been placed over hot water. Stir until chocolate melts. Add peanuts, stirring well.
Remove fondant from candy liners; dip in melted chocolate. Place on waxed paper-lined cookie sheets, and refrigerate until set.