I'm currently planning my daughter's 3rd birthday, and am looking for a simple, delicious filling to use.

I may use either the Madeira cake recipe: http://cakecentral.com/recipes/6023/madeira-cake

Or a vanilla butter cake recipe: http://cakecentral.com/recipes/4313/vanilla-butter-cake-from-the-mermaid-bakery

Still not sure which I plan on using yet, but they will be frosted with whipped cream buttercream: http://cakecentral.com/recipes/2019/whipped-cream-buttercream-frosting

Which fillings would go best with each cake? I would love something that includes fresh fruit (like strawberries) and doesn't need to be refrigerated.

Thanks in advance!