1. Preheat oven to 350º F. Line three 8-inch disposable loaf pans with parchment paper and set aside.
2. In a large bowl, whisk together the flour, baking soda, baking powder, salt and spices.
3. Cream together the butter and sugar on high, until light and fluffy, about 5 minutes. Add the eggs and beat until well combined. Stir in the bananas and vanilla extract.
4. Add the dry ingredients and blend until just combined. Use a rubber spatula to incorporate the batter as best you can from the bottom. Divide evenly among the prepared pans and bake until a toothpick inserted in the middle comes out clean, about 55 minutes to 1 hour. Remove from the oven and let cool completely.
5. To make the cream cheese frosting, beat the cream cheese, and butter until light and fluffy, about 5 minutes. Add the powdered sugar, a cup at a time, mixing well after each addition. Once all the powdered sugar has been added, add the salt milk and cream and beat on high until smooth and fluffy, about 5 to 7 minutes. Transfer to a bowl (or several bowls if you plan on coloring them with food coloring).
6. To make the royal icing, in a large mixing bowl, combine powdered sugar, meringue powder and cream of tartar. Add the water and vanilla. Beat with an electric mixer on low speed until combined; beat on high speed for 7-10 minutes or until mixture is very stiff.
7. To assemble the houses, remove the loaves from the pans. Working with one at a time, cut and stack as desired to create the base of each house and a roof. Use a serrated knife to carve out the banana bread to desired look. You can apply a thin layer of cream cheese frosting to ensure the pieces hold.
8. Once the houses have been assembled, decorate as you’d like using the cream cheese frosting, royal icing and various candies!