Preheat oven to 350 F
Melt chocolate squares and butter on low heat, take off from heat, let stand for 15 minutes
Add in beaten eggs, vanilla, salt, mix well, followed with mashed potatoes
Stir in flour
Pour batter into parchment lined pan and top with chopped chocolates and chocolate eggs
Bake for 20-25 minutes and slice once cooled to room temperature