Preheat oven to 350 degrees and line muffin tins with cupcake liners. In a large bowl, use a fork to mash the banana. Next add melted butter, coconut milk, coconut yogurt and chopped fresh pineapple together and whisk until fully combined. Add dry vanilla cake mix and blend until smooth.
Scoop batter evenly into muffin tins, filling each about 2/3 full. Place one Toasted Coconut Pineapple marshmallow into the middle of each cupcake. Bake cupcakes 17-20 minutes or until a toothpick inserted in the center comes out clean. Let cupcakes rest for 3 minutes then carefully remove from pan & cool completely.
To make the frosting, in a large bowl using an electric mixer, blend together the butter and yogurt and natural yellow dye. Add the dry frosting mix and blend a minute more until smooth and creamy. Place frosting into the piping bag with a star tip. Pipe frosting onto each cupcake and garnish with a sprinkle of toasted coconut and a piece of fresh pineapple.