Melt chocolate and milk over low heat in a saucepan. Cool slightly.
Beat butter and brown sugar until creamy. Add eggs, one at a time, while beating.
Add almond meal, flour, cocoa powder, and baking powder, and mix to combine. Add melted chocolate mixture and mix to combine.
Spoon the batter into a lightly greased muffin pan and bake for 20 minutes. Let cool.
To make the chocolate buttercream, beat butter and powdered sugar until creamed. Add cooled melted chocolate and beat to combine. Frost the cooled cupcakes and serve.
Notes
Tip: If your buttercream icing is too dry, add a splash of milk and if it is too wet, add more icing sugar.