Make the bars

1. Spritz a 9 x 13

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   pan with a little cooking spray.  Then line the pan with a sheet of parchment

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   that covers the bottom and extends up the long sides of the pan.
2. Melt the butter, chocolate chips, and marshmallows in a large pot over low heat, stirring occasionally.  It’s important to keep the heat low so that the marshmallows don’t burn.  Cover the pan with a lid or a sheet tray to help melt the marshmallows a little more efficiently.
3. Spritz a large bowl with a little cooking spray.  Mix the cereal with the coconut (if using) in the bowl.
4. Turn off the heat once the marshmallows are completely melted and smooth.
5. Pour the melted goo over the cereal and mix with a baking spatula

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   until everything is well coated.
6. Quickly scrape the coated cereal into the 9 x 13

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   .  Smooth the mixture into the pan as best you can, and then take a piece of plastic wrap, placing it on top of the bars.  Scatter the trail mix over the top of the bars.  Press with your hands to smooth and press the bars into the pan until they’re well packed and the trail mix is sticking to the top.
7. Let the bars cool and set for about an hour or as long as you can stand it.
8. Cut the cooled bars into triangles by first cutting the bars into 15 squares, and then cutting each square into 2 triangles.  Store the bars at room temperature for up to a couple days in an airtight container.