Preheat oven to 350 degrees F (175 degrees C). Grease two 9-inch round pans and line the bottoms with parchment paper.
Sift together the cake flour and salt.
Melt chocolate and butter together in a double boiler. Turn into mixing bowl, and cool to room temperature; this mixture must be cool. Mix in the sugar. Blend in egg yolks and 1 cup milk.
Pour in the flour and salt, and mix just until incorporated. Beat batter with electric mixer for 1 minute, and then blend in vanilla and 1/2 cup milk. Dissolve baking soda in the remaining 1/4 cup milk; stir into the batter quickly and thoroughly. Pour batter into prepared pans.
Bake in the preheated oven until the surface of the cakes spring back lightly when pressed with a finger, about 30 minutes. Cool cakes on wire racks.
Prepare Seven Minute Frosting, omitting vanilla (see Footnote for link). Tint the frosting a delicate pink with a few drops of food coloring, and add 1/4 cup crushed candy. Frost and fill the cooled cake. Garnish with bits of crushed candy.