1. In a large mixing bowl, combine cake mix, sugar and flour. Mix to combine.

2. Add in water, eggs, vanilla extract, and yogurt to the dry ingredients and mix well using an mixer. Mix for approximately two minutes or until well blended

3. Line the bottom of a 10 x 15-inch jelly roll pan with parchment paper spray the parchment paper with baking spray.
   

4. Divide batter equally among 2 bowls.
5. Use red and blue color paste to each bowl of batter until you get a rich color. Paste will give a darker color than standard coloring. I like to use Wilton paste.

6. Pour batter into individual sandwich sized zip-lock bags, zip to close.

7. Snip the tips off the bags and start layers of colored stripes at an angle across one pan. Alternate blue and red until complete. You will have a lot left over batter. Make another cake roll if you wish or make cupcakes with the remaining batter.

8. Bake for about 10 - 12 minutes.

9. Immediately flip cakes out of their pans, peel off the parchment paper, flip over onto a clean piece of parchment paper and immediately roll up the cake along with the parchment paper. Let it sit at room temperature for 10 minutes, then refrigerate for one hour or more until cool.

Cream Cheese Filling

1. Make the filling by beating cream cheese, powdered sugar, butter, and vanilla until well blended.

2. When the cake is cooled, unroll carefully, peeling the parchment paper off as you go.

3. Spread the frosting over the top of the cake, then tightly re-roll.

4. Refrigerate until ready to serve, cut into slices to serve.