Line a small baking pan with a parchment paper sling. I used a 10×7 baking pan. But the recipe will work in an 8×8 square baking pan, too. The burfis will be slightly thicker if you use an 8x8 pan.
Roughly break the pistachios and cashew nuts in batches, using a mortar and pestle, making sure to not powder them. Transfer to a bowl along with the sliced almonds.
Bash the cardamoms using a mortar and pestle, remove the husks, and then powder the seeds.
Break the chocolate into approx. 1" pieces and place them in a microwave safe bowl. Add the condensed milk to the chocolate.
Microwave the chocolate and condensed milk mix, in 20 seconds increments, stirring the chocolate with a spatula in between each increment, until the chocolate has melted.
Add the cashews, pistachios, almonds, cardamom powder and the ghost pepper powder to the chocolate mixture and mix well.
Pour the mixture into the lined baking pan.
Sprinkle with a pinch of sea salt.
Let it cool slightly on the counter and then refrigerate for about an hour until the mix is hardened.
Lift the hardened mix out of the pan and cut into squares or triangles. Store in an airtight container in the refrigerator for about a week.