Place chocolate in a 2-cup measure. Micro-cook, uncovered, on 100% power for 2 to 3 minutes or till melted, stirring once. Stir in corn syrup, and sweetened condensed milk. Micor-cook, uncovered, on 100% power for 45 seconds to 1 minute or till heated through. Stir in vanilla. Serve warm atop ice cream. Sprinkle with peanuts. Arranged quartered bananas around ice cream.