In a small saucepan, combine the condensed milk and cocoa powder. Set over medium heat and stir until smooth. Remove from heat and let cool slightly.
While the chocolate mixture is cooling, melt the chopped chocolate in a small microwave-safe bowl stirring every 30 seconds. Add the roasted almonds to the melted chocolate and stir to coat. Scrape the chocolate covered almonds and the melted chocolate onto a plate or small tray lined with parchment or foil. Freeze until firm. When firm, chop the almonds and chocolate and toss with the sliced marshmallows. Keep in the freezer.
In a blender, combine the cooled condensed milk mixture with the cream (or half & half), evaporated milk and vanilla. Blend until frothy.
Transfer mixture to the ice cream maker and process as directed.
For a lighter, airer ice cream, fold whipped topping into the ice cream while it's still soft (right as you remove it). Or skip this step completely and do not use whipped topping.
Stir in the chopped chocolate covered almonds and chopped marshmallows.
Scrape into pint or quart containers and freeze until firm.