Place the biscuits, walnuts, powdered sugar, and cocoa powder in a food processor. Grind on high speed until fine crumbs form.

Add the softened butter, desiccated coconut, rum extract, orange zest, and cinnamon. Continue processing until the butter is evenly distributed.

Gradually add the milk, one tablespoon at a time. Pulse the food processor after each addition and check the consistency. The mixture should be thick enough to handle easily with your hands.

Transfer the mixture to a bowl. Using your hands, break off small pieces and shape them into cylinders. Place them on a baking sheet lined with parchment paper.

Shape the cylinders into cones, creating "mountain peaks." If the peaks are too soft, chill them in the refrigerator for a few hours before glazing and serving.

Combine the chocolate and water (or milk) in a small saucepan over a double boiler. Melt the chocolate, stirring until smooth. Allow it to cool slightly (it should not be hot).

Use a spoon to pour the glaze over each peak. Once the glaze sets, sprinkle with desiccated coconut.