Preheat your oven to 350°F and lightly grease a 9x5 loaf pan*
In one bowl measure your flour, cocoa powder, baking powder, spices, and salt. Whisk to combine.
In a second, larger, bowl combine both sugars, eggs, oil, molasses, and milk. Beat with whisk or sturdy spoon until eggs are fully incorporated and the mixture is smooth and glossy.
Carefully add the dry ingredients into the wet bowl. (Just dumping it in will create a mess, so gently add it!). Using a sturdy spoon or rubber spatula, fold the dry ingredients in. When the flour is mostly incorporated, leaving only small lumps in the batter, it's finished.
Pour into your loaf pan. Place in oven and bake for 50-55 minutes. Cover after 30 minutes with foil for the remaining bake time.
When the toothpick comes out of the center clean or the cake has a springy top, remove from oven.
Allow to cool in the pan for 2 to 3 minutes, then turn out onto a cooling rack.
For the Glaze:
When the bread has cooled for at least 30 minutes, sift powdered sugar and cornstarch together in a bowl. Stir as you add in the heavy cream and continue to add until the consistency is that of light glue.
Place a plate or paper towel under the loaf, then pour the icing over the top, allowing it to drip over the edges.
Mix together the cinnamon, sugar, nutmeg, and ginger in a separate, small bowl. Using your fingers or a spoon, sprinkle the mixture over the top of the wet icing.
Allow to cool and slice when ready to serve.
Store in an airtight container until ready to eat!
*If your loaf pan is smaller be sure to only fill it 3/4 of the way. This can also be baked in a cupcake pan or a mini loaf pan with a reduced baking time.