Scant 1/2 cup packed avocado purée from a barely ripe avocado (about one small avocado)
1 tsp pure vanilla extract
Pinch fine sea salt
9 ounces good-quality dark chocolate (70% cocoa is best, but chocolate chips work, too), chopped (about 1 1/2 cups)
1/4 cup freshly squeezed orange juice (remove any large pieces of pulp)
1 Tbsp pure maple syrup
Line a miniature loaf pan about 6 x 3-inches with plastic wrap and set aside.
In the bowl of a food processor, whir the avocado purée, vanilla and salt. Set aside while you melt the chocolate.
In a heavy-bottomed pot set over the lowest heat possible, combine the chocolate, orange juice, and maple syrup. Stir constantly until melted and smooth, about 5 minutes. Immediately scrape the chocolate mixture into the food processor with the avocado, and blend again until perfectly smooth and glossy. Turn the mixture into the loaf pan and smooth the top.
Refrigerate, uncovered, until the top is firm and dry; then cover the top with more plastic wrap and refrigerate until the entire loaf is firm, 4 to 6 hours or overnight.
To unmold, remove plastic from the top of the loaf. Invert over a serving dish and remove the loaf pan, then carefully peel away the plastic. Serve in thin slices with fresh berries.