Preheat oven to 350 F. Line a 12 cup muffin pan with paper liners. In a large bowl, whisk together flour, sugar, salt, and baking powder. Add in milk, oil, eggs, and vanilla extract. Whisk until smooth.
Evenly divide cupcake batter between the liners. Bake for 15-18 minutes. Let cool completely.
For the frosting, in a large bowl with a mixer beat softened butter with powdered sugar, milk, and vanilla extract until smooth. Evenly spread frosting onto each cupcake.
Decorate with chocolate chips and candy.
