Heat oven to 180ºC F. In 2 litre saucepan combine butter and unsweetened chocolate. Cook over medium heat, stirring occasionally, until melted. Stir in remaining brownie ingredients. Spread batter into greased 23 cm pie pan. Bake for 20 to 25 minutes or until brownie is firm to the touch. Meanwhile, in 1 litre saucepan cook caramels and whipping cream over medium low heat, stirring occasionally, until caramels are melted.Remove brownie from oven; spread melted caramel mixture over entire baked brownie. Sprinkle with pecans and chocolate chips. Return to oven; bake for 3 to 5 minutes or until caramel mixture is bubbly. Let stand 30 to 45 minutes, cut into wedges. Serve warm with Ice cream.