Slowly melt the unsweetened chocolate and cacao butter together in a large bowl over simmering water (double boiler).
Remove from heat and add all remaining ingredients to the melted chocolate. Using an electrical hand or stand mixer, mix ingredients until fully combined.
Line a muffin pan with paper muffin cups and fill with mixture almost to the top.
Bake in a preheated oven to 325°F for about 25 minutes or until set.
Set pan on a wire rack to cool, then transfer to the refrigerator and allow it to chill for at least two hours.
Top cheesecake with melted dark chocolate and fresh raspberries if desired.
1 oz of chocolate is the same thing as 3 tablespoons of finely shaved chocolate. You can shave the chocolate using a sharp knife or a grater. To measure 2 tablespoons of cacao butter use the same method.