Preheat the oven to 350°F/170℃ and prepare a loaf pan. Spray and line a 9x5 loaf pan with a neutral cooking spray and line with parchment paper. Make sure that the oven rack is in the middle of the oven.
Make the flax egg. In a small mixing bowl, combine the flax seeds with boiling water. Mix well and let rest for 5 minutes.
Mix the wet ingredients. In a large mixing bowl, combine the milk, melted butter, sugar, flax egg, molasses, and vanilla. Whisk together well.
Sift the dry ingredients. Sift the flour, salt, cornstarch, baking powder, ginger, cinnamon, all spice, and cloves together.
Combine. Combine the dry ingredients into the wet ingredients. Whisk well, switching to a spatula to make sure that all the ingredients on the sides of the bowl are incorporated.
Transfer. Carefully pour the batter into the prepared loaf pan. Smooth the top out with the spatula.
Bake. Bake the cake in the preheated oven for 60 to 65 minutes. Do not open the oven door for the first 40 minutes of baking no matter what. This will cause the cake to sink. Using a glass pan is really helpful for making sure the cake edges are not burning. The cake will be done when a toothpick inserted into the middle of the cake removes cleanly.
Cool. Remove the cake from the oven and let it rest in the hot pan for 10 minutes. Then, using the parchment paper, remove the cake from the pan and let it cool on a wire cooling rack. I like to pop my cake in the fridge to help it chill.
Make the icing. In a small mixing bowl, combine the powdered sugar, vanilla extract, and water. Mix until thick with a pourable consistency. Pour over the cooled cake, letting it drip down the edges. Serve right away, or, place in the fridge to let the icing harden. Enjoy!
