Cupcakes:
1/2 cup unsalted butter, at room temperature
2 T citrus olive oil (I used plain EVOO)
1 cup sugar
2 T vanilla
2 eggs
Zest of 1 orange
2 cups all purpose flour
1/4 tsp baking soda
1/4 tsp baking powder
1/4 tsp salt
3/4 cup heavy cream
1/4 cup orange juice, freshly squeezed

Marshmallow Cream Filling:
7 oz marshmallow fluff/cream
1/2 cup unsalted butter, at room temperature (I used 3/4 of a stick rather than the whole stick for this part, could probably use even less)

Orange Buttercream:
1/2 cup unsalted butter, at room temperature
1/8 - 1/4 cup orange juice, freshly squeezed
Zest of 1 orange
1/4 tsp vanilla extract
4 cups powdered sugar (I used just over 3 cups for mine)
Also - I added food coloring to make the frosting more orange (2 drops red, 6 drops yellow) Also 1/4 cup of juice was 1 orange for me - so I used 2 total.