Preheat oven to 350 degrees F. Grease an 8 ½ by 4 ½ inch loaf pan and line with a strip of parchment paper.
Combine cocoa and chopped chocolate in a 2 cup Pyrex measuring cup or a small microwave-safe bowl. Pour very hot coffee over and stir until chocolate melts. You shouldn’t need to, but if for some reason the chocolate doesn’t melt all the way you can microwave it for 20 seconds and stir. Let cool
In a second bowl, stir together flour, salt, and baking soda. Set aside.
With an electric mixer beat the butter, sugar, and vanilla on medium speed for about 2 minutes or until creamy and fluffy. Reduce speed to medium and add eggs one at a time, mixing about 30 seconds after each egg. Also add the 2 tablespoons of egg.
Stir in the sour cream, then stir in the flour mixture and the melted chocolate mixture alternately, stirring by hand (or using lowest speed of mixer if you prefer) until blended. Add chocolate chips.
Scrape batter into prepared pan. Bake until wooden skewer inserted into center comes out with few crumbs attached, 48 to 52 minutes. An internal thermometer should be over 200 and rising. Let cool completely.
To make the glaze, chop the 56 grams of dark chocolate. Put ½ tablespoon coffee (or water), ½ tablespoon of corn syrup and 1 ½ tablespoon of heavy cream in a microwave-safe glass measure (2 cup Pyrex). Heat for about 30 seconds or until it begins to boil. Add the chopped chocolate and let sit for a minute, then stir until melted and smooth. Spread over top of cake. Sprinkle with candies.