2) Stir in 90g of the icing sugar.
3) Heat until the mixture measures 230 degrees C on a sugar thermometer, stirring often, then turn off the heat.
4) When the temperature begins to drop, add the remaining icing sugar. Whisk with a hand mixer set on high speed, for 1-2 minutes, until the mixture cools and thickens and can no longer be whisked. Let the mixture cool in the pan for 10 to 15 minutes, or until cool enough to touch. Don't let it sit too long - the mixture should still be pliable enough to shape.
5) Take a teaspoonful and roll it between your palms or on a clean work surface, until it forms a roll about 1 cm thick and 11cm long. Repeat with the remaining mixture and place the rolls on waxed paper. You should have 8 rolls. Leave the rolls to firm up for 1 to 2 hours.
6) Combine the 20 toffees with the water in a small saucepan over low heat, stirring often, until the caramels melt completely. Turn off the heat. If you work fast this caramel will stay warm while you make the candy bars.
7) Pour the peanuts onto a baking sheet or other flat surface. Using a pastry brush and working quickly, paint a coating of caramel onto one side of a centre roll. Quickly turn the centre over, caramel side down, and press gently down into the peanuts, so that they stick to the surface of the candy. Paint more caramel onto the other side of the roll and press it down onto the peanuts once more. The candy should have a solid layer of peanuts covering all sides. If needed, brush additional caramel onto the roll, then turn it onto the peanuts to coat the roll completely. Place the candy bar onto waxed paper, and repeat with the remaining centres. Place the bars into your refrigerator for 1 to 2 hours so that they firm up.
8) Pour the milk chocolate chips into a glass or ceramic bowl and zap it in the microwave for 2 minutes on 50 percent power. Gently stir the chips, then heat for an additional 30 seconds at 50 percent power. Repeat if necessary, stirring gently after each 30 seconds. Don't over-cook the chips or the chocolate will burn and seize.
9) Drop a candy bar centre into the melted milk chocolate and cover the candy bar with chocolate using 2 forks, 1 in each hand.
10) When the candy is covered with chocolate, balance the bar on both of the forks, one at each end of the candy bar, and tap the forks on the top edge of the bowl so that much of the chocolate drops off. Carefully place the candy bar onto waxed paper and remove the 2 forks. Repeat with the remaining ingredients, and then chill the candy bars until firm.