Preheat the oven to 350 degrees Fahrenheit.
Add 1 cup of chocolate chips to a bowl with the coconut oil. Melt in the microwave at 30 second intervals, stirring between each. let cool for a few minutes.
Meanwhile, beat together the eggs, sugar and vanilla with an electric mixer. Beat in the chocolate once it has melted and cooled slightly.
Fold in the cocoa, tapioca and salt until well combined.
Fold in the remaining 1/2 cup of chocolate chips.
Transfer to an 8x8 pan lined with parchment paper. Bake for 22-28 minutes. I usually do 25 minutes, but the longer you do the more set/well done the center will be if that's what you prefer.
Let cool, then slice around the edge so the parchment will easily lift out of the pan. Cut into 16 squares and enjoy!