First, start the frosting. You have to do this at least a few hours before you will make the cake, ideally the day before!!
In a small pot, combine the 1 cup of white chocolate chips and 1 cup of butter. Heat on medium-low until everything is smooth and melted.
Let mixture come to room temperature, then cover and place in fridge until completely solid, ideally overnight.
Preheat the oven to 350F, and grease/flour two 6" cake pans.
In the bowl of a stand mixer, combine the flour, baking powder, baking soda, salt, and sugar. Add in the butter, and beat on low until it's incorporated and has a sandy texture.
In a small bowl, whisk together the oil, eggs, sour cream, vanilla and almond extract, and add them to the dry ingredients. Mix until combined.
Pour in the milk, and beat on medium-low until smooth and creamy.
Finally, stir in the fresh cranberries and white chocolate chips.
Divide batter evenly among the two pans, and bake for 40-45 minutes, until a toothpick inserted in the center of the cake comes out with just a few crumbs. Let cakes cool completely before decorating.
When ready to decorate, grab the solid white chocolate and butter mixture for the frosting, and place in a stand mixer fitted with the paddle.
Beat the mixture until completely soft and fluffy. It will take a few minutes until it really comes together! Now it is ready to use.
To make the white ganache, combine the white chocolate/almond bark and heavy cream in a microwave-safe bowl. Heat in 15 sec increments until smooth and creamy. Let cool slightly, then place in a ziplock baggie or a squeeze bottle, and decorate as desired.
To assemble the cake, divide the 2 cake layers in half to create 4 thin layers. Place one cake piece on your cake stand or platter, and pipe frosting all over. Smooth with an offset spatula if desired. Repeat with all.
Pipe frosting all over the outside of the cake, and smooth using a bench scraper.
Decorate the top and sides with the white chocolate ganache you made. Finally, add some rosemary sprigs on top and decorate with fresh or sugared cranberries.
Enjoy immediately or place in fridge until needed.