Remove cupcakes from pan, cool completely on wire racks.

In a small saucepan, whisk flour into milk until there aren't any lumps. Heat milk and flour on medium low heat, stirring constantly until mixture thickens to a gravy like consistency. Spoon mixture from hot pan into a small bowl. Cover with saran wrap. Allow to cool to room temperature. In a mixing bowl, cream shortening and sugar about 5 minutes. Add cooled milk-flour mixture, beat until fluffy and sugar is dissolved completely, about 5 minutes (Be sure to beat until the grains of sugar are dissolved) ( If in doubt, whip some more) Add vanilla and powdered sugar. Beat well.

Once cupcakes are fully cooled, place filling into a frosting bag with a star tip (#18), press the tip down into the middle of each cupcake, give a good squeeze to the bag, enough to cause the top of the cupcake to rise, but not enough to cause it to crack. (No worries if it does crack, the frosting will cover it)

Frost cupcakes with funfetti frosting and top with hearts and candy