Line a 13x9-in. pan with foil and grease the foil with 2 teaspoons butter; set aside., In a large heavy saucepan over medium-high heat, melt remaining butter. Stir in sugar and evaporated milk. Bring to a boil; cook and stir 5 minutes longer. Remove from the heat; cool for 5 minutes. Stir in chocolate chips until melted. Stir in marshmallow creme and vanilla until smooth. Spread into prepared pan; set aside., In another large heavy saucepan, combine the brown sugar, corn syrup, butter and salt; bring to a boil over medium heat, stirring constantly. Cook 4 minutes longer without stirring., Remove from the heat; gradually stir in condensed milk. Return to the heat. Reduce heat to medium-low; cook and stir until a candy thermometer reads 244° (firm-ball stage). Remove from the heat; stir in vanilla. Pour over chocolate mixture (do not scrape saucepan). Refrigerate until caramel is set, at least 2 hours., Using foil, lift candy out of pan. Gently peel off foil; cut into 3-1/4x1-in. bars. In a microwave, melt candy coating; stir until smooth. Dip bars in coating; allow excess to drip off. Place on a waxed paper-lined baking sheet; refrigerate until set. Store in an airtight container.