In a medium sized bowl, combine the sifted confectioners sugar and powdered milk. Set aside.
In a medium saucepan, combine the granulated sugar, corn syrup and butter. Bring to a boil on high heat, stirring constantly. Once it reaches the boiling point, reduce heat to medium and continue stirring for about 5 minutes, stirring occasionally. Stir in the vanilla extract and remove from heat.
Add the confectioners sugar and powdered milk mixture to the wet ingredients; stir well until the mixture is thoroughly incorporated and smooth.
Let the dough cool until it is firm to handle, about 30 minutes to an hour (leave in saucepan)
Divide the dough into three equal parts(I did four, I added black) and set into separate bowls. Add food coloring to each bowl as necessary. Leave one dish uncolored. Knead the dough until color is mixed, refrigerate if it starts feeling too soft or sticky.
On top of a sheet of waxed paper or parchment, use your hands to roll out each color of dough into a long, slender rope. You can roll it out to your desired thickness; for larger candies, make the rope thicker.
Line the three ropes of dough together. To ensure they will stick together, lay a piece of waxed aper on top and give them a very gentle rolling with a rolling pin. You just want to adhere them, not flatten them.
Using a sharp knife, cut the dough into triangles. Let the finished kernels sit for hours, days even to firm up.