Line an 8-inch square pan with nonstick foil or parchment paper.
Lay graham crackers across the bottom of the pan.
Heat the caramel bits and milk in microwave-safe bowl on high for 2 minutes or until caramel bits are completely melted and mixture is blended, stirring every 30 seconds. Alternatively, you can melt the caramels and milk together in a small saucepan.
Pour melted caramel over graham crackers and sprinkle with peanuts, marshmallows and pretzels.
Melt the chocolate in the microwave by heating on high and stirring every 30 seconds. Drizzle over the bars.
Refrigerate until set. Lift from pan and cut into squares.