Preheat the oven to 350 degrees.
In a large bowl combine the flour, salt, and baking powder. Mix and set aside.
In another large bowl cream the butter and sugar. Add in the vanilla and eggs and mix well. Stir in the white chocolate pudding mix.
Pour the flour mixture into the butter mixture and mix until well combined.
Add several drops of red food coloring and mix until evenly colored.
Place 1-2 teaspoons of batter on an ungreased baking sheet. Bake for 9-10 minutes. Remove from oven and cool for 2-3 minutes before removing to a wire rack. Cool completely.
Meanwhile, beat the butter for the frosting until smooth. Add in the cocoa powder and mix until combined.
Add the powdered sugar, 1/2 cup at a time, until totally mixed. Add in enough milk to make desired consistency. Stir in vanilla.
Put the chocolate frosting into a piping bag or zip top baggie and pipe onto half of the cookies. Top with remaining cookies.
If desired, pour the sprinkles into a shallow dish. Roll the edges of the cookie frosting into the sprinkles.