Grease 15x10x1" jelly roll pan and line with parchment paper.
Grease and flour paper.
Combine cake mix, eggs, yogurt and vegetable oil and beat until well blended.
Spread batter into pan (there will be batter remaining).
Tap gently on flat surface to remove any trapped air bubbles.
Bake for 15 minutes or until toothpick inserted in middle comes out clean.
Spread kitchen towel out on countertop and cover with a sheet of parchment paper lerger than cake.
Dust parchment paper with powdered sugar.
Carefully flip cake from pan onto prepared parchment paper.
Remove pan and parchment paper used during baking.
Starting at a short end, roll up cake with parchment paper and towel inside.
Place on wire rack to cool for 25-30 minutes.
In a large bowl, cream the butter and add vanilla (and red food coloring if desired).
Mix in the sugar one cup at a time.
Beat in the milk mixing until fluffy.
Unroll cake, removing paper and towel (cracks and breaks should fit back together when you reroll).
Spread cake with buttercream icing and roll back up.
Refrigerate at least 30 minutes.
Mix together whipped topping and dry pudding mix until well mixed.
Place roll on serving plate.
Spread topping mixture all over roll.
Sprinkle with candy decorations.
Refrigerate at least 2 hours.
Cut into slices and serve.