Preheat the oven to 180°C and line a muffin tray with paper liners. In the bowl of an electric mixer beat the butter and sugar on medium high speed for 5 minutes until pale and fluffy.
Add in the eggs, one at a time, scraping down the sides of the bowl as necessary. Add in the vanilla.
Add in the vegetable oil, flour and cocoa powder and mix until combined. Add in the red gel color until fully incorporated.
Divide the batter amongst the liners and bake for 20-25 minutes until a toothpick inserted comes out clean.
While the cupcakes cool make the filling. In the bowl of an electric mixer beat the marshmallow fluff and butter together. Add in the powdered sugar and milk and beat until fluffy.
Once the cupcakes are completely cool cut a cone shape in the center and fill with the marshmallow filling. Spread a thin layer of marshmallow on top.
Let the marshmallow set about 10 minutes. Make the chocolate glaze. In a microwave safe bowl heat the chocolate at 30 second bursts until melted. Stir in the butter and milk. Microwave again for 10-20 seconds. Stir. The mixture should be slightly thick and glossy.
Dip each cupcake in the chocolate or spoon the chocolate on top. Microwave the chocolate for 20 seconds if it starts to cool down. Once dipped allow the chocolate to set.
Once the chocolate is set draw the loopy squiggles across the center with red icing or glitter gel.
Recipe courtesy of An American Cupcake in London.