1. Preheat oven to 350°F (175°C) and line an 8 or 9-inch square pan with parchment paper, depending on how thick you want your chocolate bars to be.

2. In a large bowl, beat the butter and peanut butter together until light and fluffy. Add in the sugars and cream together until smooth.

3. Beat in the the egg and vanilla extract.

4. In a separate bowl, whisk together the flour, baking soda, and baking powder until well combined.

5. Stir the dry ingredients into the butter mixture, stirring until just combined.

6. Fold in the peanut butter and white chocolate chips.

7. Press the dough into the parchment lined pan and bake for 15 – 20 minutes, until just browned around the edges and set in the middle. Let the cookie base cool completely on a wire rack before adding the caramel topping.

For the caramel:
1. Place the sugar in a medium saucepan and drizzle the water over it.

2. Cook over low heat, watching closely to ensure the caramel doesn’t burn. The sugar will slowly caramelize and turn a deep golden brown. Do not stir the sugar as it cooks, as this will cause your sugar to crystallize and prevent it from caramelizing. If you notice the sugar is cooking faster around the edges, simply hold the pan firmly by the handle and swirl the sugar in the pan gently. You can also use a pastry brush dipped in water to carefully brush down and stray sugar crystals around the edges of the pan.

3. Once all the sugar has melted and caramelized, add the butter a few cubes at a time, stirring it in gently with a wooden spoon. Be careful as you do this, as the caramel will be very hot and may sizzle and splatter when you add the butter.

4. After you stirred in all of the butter, add the salt and continue to cook the mixture for another two minutes.

5. Remove the saucepan from the heat and add the cream, stirring it in until well combined.

6. Pour the caramel sauce into a bowl and transfer to the fridge to let it cool for at least 30 minutes before adding to the cookie base.

To assemble:
1. Using a lollipop stick, or a toothpick, poke holes in the surface of the cookie base, then pour the caramel sauce overtop. Sprinkle with salted peanuts and transfer to the fridge to let the bars set, at least 1 hour.

2. Once the bars have set, remove the pan and gently peel off the parchment paper. Slice into bars. These chocolate bars will be very rich, so you may want to keep them small.

3. Line a baking sheet with parchment paper and set aside.

4. In a heat-proof bowl over a pot of simmering water, or in a double boiler, melt the chocolate. Once completely melted, remove from heat.

5. Using a fork, dip each of the bars into the melted chocolate, making sure to coat them completely. Gently place the dipped bars on the parchment-lined baking sheet. Let the coating set before serving immediately, or store in an airtight container at room temperature for up to four days, or in the fridge for a week. Chocolate bars will keep in the freezer for up to one month.