Preheat oven to 350 degrees.
In the bowl of your mixer, add cake flour, baking powder and granulated sugar and mix on low.
Next add in butter substitute and coconut milk and blend until well mixed.
Add in vanilla extract and olive oil and mix well.
Turn off mixer and fold in egg whites.
Lastly, whisk in fruity pebbles.
Add cupcake liners to cupcake pan.
Using an ice cream scooper, scoop mixture into cupcake liners.
Bake cupcakes for 17-21 minutes or until toothpick inserted in the center comes out clean but DON'T OVERBAKE. Because these cupcakes don't have any egg yolks, they have a tendency to dry out faster.
Remove cupcakes from oven and allow to cool on cooling rack.
While cupcakes cool, add cup of butter substitute to bowl of mixer and slowly add in powdered sugar, coconut milk and vanilla extract then slowly increase speed of mixer and beat until well mixed buttercream is formed.
Pipe buttercream on top of completely cooled cupcakes.
Sprinkle tops of buttercream with fruity pebbles and serve.