In a separate bowl, clean and slice strawberries. Add sugar; mix well. Allow strawberries and sugar to blend together; strain strawberries separating them from any juices that have formed. You don’t want the strawberry juices to make your cake soggy.
To assemble the cake, place one layer of cake on a cake stand or plate. Spread half of the Nutella or prepared chocolate frosting over the layer, drizzle with the glaze. Then top with half of the sweetened strained strawberry filling, bringing it to the edge, and finally drizzle with a bit more glaze over the strawberry filling, allowing it to drip over the sides.
Take the second layer of cake and place it on top of the filling. Top the cake with the remaining nutella or prepared chocolate frosting, and sweetened strained strawberries, drizzle the rest of the glaze over the cake, making sure it drips down the sides. Lightly sprinkle slivered toasted almonds over the top.