1
: Beat 1 cup (250 mL) butter, sugar and salt until fluffy. Add flour; mix well. With floured fingers, press evenly into greased 9" (23 cm) square pan. Bake in preheated 350°F (180°C) oven 30 minutes or until lightly browned. Cool slightly.
2
: In 2-quart (2 L) glass measure with handle, in microwave oven, melt remaining 1/2 cup (125 mL) butter on High (100%) 1 minute.
3
: Stir in Eagle Brand and corn syrup. Microwave on High (100 %) 6 to 8 minutes, stirring after each minute or until mixture turns a light caramel colour. Stir in vanilla.
4
: Spread over warm shortbread. Drizzle with chocolate. Chill until firm. Cut into bars. Store covered at room temperature.