Preheat the oven to 375 degrees F. Line a baking sheet with parchment paper or a silpat.
Pour the almonds onto the baking sheet. Roast, the almonds halfway through, until the almonds are fragrant, about 10-12 minutes. Watch closely to make sure they don’t burn.
In the meantime mix together the coffee grounds, cocoa powder and salt. Add the melted coconut oil and vanilla to a small bowl. When the almonds are done roasting add the pistachios to the baking sheet. Toss the nuts with the coconut oil and then toss them with the coffee. Toss well making sure the coffee grounds evenly coat the almonds and pistachios. It will seem like a lot of coffee, but this is what you want!
Roast the almonds + pistachios until the coffee is fragrant and the almonds are starting to become crisp, about 10 minutes. Remove from the oven and let cool.
Line a sheet pan with parchment or wax paper.
Melt the dark chocolate in a double boiler or a heatproof bowl set over a pan of simmering water, stirring until melted.
Pour 3/4 (leaving about 1/4 of the chocolate for drizzling over top the nuts) of the melted chocolate on to the prepared baking sheet that has been lined with wax or parchment paper and spread the chocolate out to form a rectangle, be careful not to make it too thin. Immediately sprinkle on half of the toasted coconut, then sprinkle on the almonds and pistachios, leaving out most of the coffee grounds. If desired, sprinkle the bark with a few tablespoons of the coffee grounds that were left on the baking sheet (I probably used about 1/4 cup). Add the remaining toasted coconut and then drizzle the remaining melted chocolate overtop of everything. Sprinkle with sea salt if desired. Refrigerate until firm, about 30 minutes to 1 hour. Peel off parchment, and break bark into pieces.
*The bark can be kept in an airtight container at room temperature for up to 4 days or refrigerated for up to 2 weeks.