Preheat the oven to 325°F. Spray a 9 x 5-inch metal loaf pan with nonstick cooking spray.
Place the 1 cup of milk chocolate chips in a microwave-safe bowl. Heat in 30-second intervals, stirring between each, until smooth. Set aside to cool slightly.
In a medium bowl, whisk together the flour, cocoa powder, baking soda, and salt.
In the bowl of a stand mixer fitted with the paddle attachment, beat the eggs and sugar until light and fluffy, about 5 minutes.
With the mixer on low, add the melted chocolate, vegetable oil, and water. Mix until smooth.
Gradually add the dry ingredients, mixing just until combined.
Fold in the cranberries and semisweet chocolate chips.
Pour the batter into the prepared loaf pan and smooth the top.
Bake for 80 to 90 minutes, beginning to check at about 75 minutes. A toothpick inserted into the center should come out with a few moist crumbs but no wet batter.
Let the loaf cool completely before adding the ganache.