In a small bowl, add the chocolate chips and oil and microwave in 30-second increments until the chips have melted. This usually takes a minute in my microwave. Next, line your molds with one layer of melted chocolate. Add 2-3 tablespoons of the melted chocolate into the mold and spread it out. Use a pastry brush or the back of a spoon. Freeze while you prepare the filling.
Prepare the filling
Make the pistachio butter by adding 2 cups of raw, unsalted, and shelled pistachios to a food processor, grinding till you have a smooth and runny butter. This can take 10-15 minutes. Please note that you may need to stop in between as the food processor can heat up. Set aside.Crush the rice chex into smaller pieces. I usually add them to a zip-top bag and crush them with a rolling pin or my hands. Then, add the chex, pistachio butter, maple syrup, and tahini to a small bowl and mix until combined.
Take the molds out of the freezer and divide the filling between the two. Using the back of a spoon or an icing spatula, pack it in tightly and then pour more melted chocolate over the top. Use a pastry brush, icing spatula, or the back of a spoon to spread and smooth the chocolate evenly. Place them back in the freezer for 10-20 minutes to set completely.
Unmold the chocolate, sprinkle with sea salt if using, and give it 2-5 minutes to rest before biting in!
Video
Notes
Make sure your Rice chex is gluten-free. Rice crispies were my first choice, but they have malt as an ingredient. Malt is made with wheat.
Pistachio butter can be made at home or buy-one ingredient pistachio butter from the store. The original recipe uses pistachio cream that contains sugar and other additives so I prefer to use pistachio butter. To make pistachio butter at home, add 2 cups of unsalted, unroasted, shelled pistachios into a food processor and grind till you get a runny butter. This usually takes 10-15 minutes. If using store-bought pistachio butter, add 7-8 ounces.
The success of this chocolate bar depends heavily on the chocolate, so make sure to use the best quality chocolate available.
Don't skip the freezer time. You want the chocolate to set completely before unmolding it.
Use a silicone mold for best results. It comes off much cleaner than plastic molds. If you can't find a silicone mold, use a parchment-lined loaf pan to get a similar shape.