Preheat oven to 325 degrees Fahrenheit. Line a baking sheet with parchment paper and spray lightly with nonstick cooking spray.
In the bowl of an electric mixer, beat egg whites until soft peaks form.
Add one and half teaspoons vanilla extract and slowly add granulated sugar, beating until stiff peaks form.
Fold in salt and ground nuts, one-quarter cup at a time.
Spread mixture in two even circles on the prepared baking sheet. Bake 20 to 25 minutes, until dry. Let cool.
In the bowl of an electric mixer, beat heavy cream with confectioners’ sugar and two tablespoons vanilla extract until stiff peaks form.
In a double boiler or in 30-second increments in the microwave, melt chocolate with oil.
On a baking sheet lined with parchment paper, spread melted chocolate in a rectangle. Refrigerate to cool and set.
Once set, break into shards.
Carefully peel cooled cake circles off parchment.
Reserve a heaping spoonful of filling. Spread remaining filling over the first circle and top with the second circle.
Spread reserved filling on top and insert chocolate shards so they stand upright.
Multitask! While the cakes cool, prepare the filling and chocolate shards.