Ingredients
For the crust: one cup unsalted butter (two sticks), half cup granulated sugar, and two cups graham cracker crumbs.
For the caramel layer: one cup unsalted butter (two sticks), half cup light corn syrup, and one can (14 ounces / 397 grams) sweetened condensed milk.
For the topping: two cups semi-sweet chocolate chips, one cup creamy peanut butter (optional but recommended), and one cup chopped roasted peanuts (or toasted pecans, almonds, or toffee bits).
Equipment Needed
A 9×13 inch (23×33 cm) baking pan, parchment paper, a medium saucepan, a large saucepan, a wooden spoon or silicone spatula, and a microwave-safe bowl.
Method
Line a 9×13 inch baking pan with parchment paper, leaving some overhang on two sides for easy removal.
Make the crust. In a medium saucepan over medium heat, melt one cup of butter. Stir in the granulated sugar and graham cracker crumbs. Mix until everything is well combined and the crumbs are evenly moistened.
Press the crust mixture firmly and evenly into the bottom of the prepared pan. Use the bottom of a measuring cup or a flat spatula to press down very firmly. Set aside.
Make the caramel layer. In a large saucepan over medium heat, combine one cup of butter, the corn syrup, and the sweetened condensed milk. Stir constantly with a wooden spoon as the mixture comes to a gentle boil.
Reduce the heat to medium-low and continue stirring constantly. Cook for five to eight minutes until the caramel thickens and turns a deep golden brown. The mixture should reach the soft-ball stage (about 235°F / 113°C on a candy thermometer) if you have one. Do not stop stirring or the caramel will burn.
Immediately pour the hot caramel over the graham cracker crust. Spread it evenly with a spatula. Let the caramel layer cool and set for about fifteen minutes at room temperature, or place the pan in the refrigerator for ten minutes to speed up the process.
Make the chocolate topping. In a microwave-safe bowl, combine the chocolate chips and peanut butter (if using). Microwave in thirty-second bursts, stirring after each, until smooth and glossy.
Pour the melted chocolate over the cooled caramel layer. Spread it evenly with a spatula. Immediately sprinkle the chopped peanuts (or your chosen topping) over the wet chocolate, pressing down gently so they stick.
Refrigerate the bars for at least two hours until all layers are completely firm and set.
Once firm, lift the bars out of the pan using the parchment overhang. Place on a cutting board. Use a sharp knife to cut into small squares or rectangles. These bars are rich, so smaller pieces are recommended.
Store in an airtight container in the refrigerator.
Storage
Store in an airtight container in the refrigerator for up to two weeks. These bars can be frozen for up to three months. Layer them between sheets of parchment paper in a freezer-safe container. Thaw in the refrigerator before serving.
Variations
For a nut-free version, omit the peanut butter and peanuts. Use chocolate chips only for the topping and sprinkle with crushed pretzels, toffee bits, or additional graham cracker crumbs. For a salted caramel version, sprinkle a generous pinch of flaky sea salt over the caramel layer before adding the chocolate. For a white chocolate version, use white chocolate chips instead of semi-sweet and top with dried cranberries and chopped pistachios. For a coconut version, add one cup of toasted shredded coconut to the crust or sprinkle it over the chocolate topping. For a mint chocolate version, add half a teaspoon of peppermint extract to the melted chocolate.
Serving Suggestions
Serve with a glass of cold milk, alongside a cup of hot coffee or espresso, as part of a holiday cookie platter, or wrapped in cellophane bags as homemade gifts.
Tips for Best Results
Press the crust very firmly. A loose crust will crumble when you cut the bars. Use the bottom of a measuring cup to apply firm, even pressure.
Do not stop stirring the caramel. Caramel made with sweetened condensed milk and corn syrup can burn easily. Stir constantly from the moment it starts to bubble until you pour it into the pan.
Use a candy thermometer if you have one. The caramel should reach the soft-ball stage (235°F / 113°C). This ensures the perfect chewy, not-runny texture. If you do not have a thermometer, cook until the caramel is thick and deep golden, about five to eight minutes of steady bubbling.
Let the caramel cool slightly before adding the chocolate. If the caramel is still very hot, it will melt the chocolate layer and create a muddy swirl instead of clean layers. Fifteen minutes at room temperature is enough.
Use good quality chocolate. Cheap chocolate chips contain stabilizers that can make the topping less smooth. Ghirardelli, Guittard, or Nestlé Toll House work well.
Cut the bars while they are cold. Straight from the refrigerator gives the cleanest cuts. For extra clean edges, run your knife under hot water, wipe it dry, and cut. Wipe the blade clean between each slice.
Make them ahead. These bars need at least two hours to set, but they are even better the next day. Make them a day or two before you need them.
Do not skip the peanut butter in the chocolate layer (unless you need nut-free). The peanut butter softens the chocolate slightly, making it easier to cut and giving a Reese’s-like flavor. If you skip it, the chocolate layer will be harder and more prone to cracking.