Special equipment: a candy thermometer
Preheat the oven to 350 degrees F. Brush an 8-by-8-inch dish with 1 teaspoon of the coconut oil and set aside.
Combine the coconut flakes, hazelnuts, walnuts, cashews, trail mix and flaxseed and spread into an even layer on a baking sheet. Toast until lightly golden, 10 to 12 minutes, then transfer to a large heatproof bowl. Set aside.
In a small saucepan, combine the maple syrup, honey and 1/2 teaspoon salt and bring to a boil over medium-high heat. Cook, stirring occasionally, until the temperature on a candy thermometer reads 260 degrees F, about 5 minutes. Immediately pour over the nut mixture and stir to coat. Use a rubber spatula to press the mixture into the prepared dish and let cool until set, about 30 minutes.
To make the chocolate drizzle, combine the chocolate chips and remaining 1 teaspoon coconut oil in a medium heatproof bowl and place over a small pot of simmering water. Heat, stirring, until melted and smooth. (Alternatively, combine the chocolate and oil and microwave in 15-second intervals, stirring often, until melted and smooth.)
Drizzle the chocolate over the mixture. When set, cut into bars and serve.