For the cupcakes: Preheat the oven to 350 degrees F. Use a 24 socket cupcake pan and line with paper liners. Set the pan aside.
In a medium bowl, whisk together the flour, baking powder and salt.
In a large bowl of an electric stand mixer using a paddle attachment, combine the butter, sugar and cocoa powder, mixing until blended.
Add the eggs and yolk, and beat on low speed until all ingredients are smooth and blended.
Decrease the speed of the mixer to slow and add half of the dry ingredients.
Mix for 1 minute, scraping the sides of the bowl occasionally.
Add the banana puree and buttermilk to the batter, beating for 30 seconds. Then add the rest of the dry ingredients. Divide the batter evenly into the prepared cupcake liners and bake on the center rack until a cake tester inserted into the center of each cake comes out clean, 20 to 25 minutes. Cool the cakes in the pans for 10 minutes.
Remove from the pans and cool the cakes completely on wire racks, about 30 minutes.
For the buttercream: In a small saucepan, cook the caramel candies, bananas, milk and salt together until thoroughly melted; the mixture will be clumpy.
In an electric mixer with the whisk attachment, whip the yolks and sugar. Continue to whip on high speed until light and fluffy.
Pour the hot caramel mixture into the yolks with the mixer going. Continue to whip until cool.
Cut up the butter and add (slowly). Then add the vanilla. Use immediately, or keep refrigerated until ready to use.
For the filling: Cook together the sugar and 1/2 cup water, developing a medium caramel.
Heat up the cream until boiling. Slowly add the hot cream to the caramel mixture. Continue to cook until smooth and all the lumps are out. Stir in the dulce de leche, molasses and salt.
For the white chocolate paint: Make a ganache out of the chocolate and cream by heating up the cream in a small saucepan and pouring over the white chocolate.
Whisk together until smooth. Divide the ganache into 3 portions and using desired food color, tint each batch the desired color. Use the microwave to reheat if the mixture gets too thick.
To assemble: Using a melon baller, remove the core from the center of each cupcake. Fill each cupcake with the salted butterscotch filling. Using a pastry bag with a #802 tip, ice each cupcake with a generous layer of the caramel banana buttercream. Use 3 colors of white chocolate paint and garnish with 3 blue men heads on top.
