S'Mores Cake Roll - cooking recipe

Ingredients

For graham cracker cake
4 large egg yolks, at room temperature
1 cup sugar
1/3 cup honey
1/4 cup water
1/4 cup vegetable oil
1/4 cup butter, melted and cooled
1/2 cup whole wheat flour
1/2 cup all-purpose flour
1 teaspoon baking soda
1/2 teaspoon baking powder
1/4 teaspoon salt
1/8 teaspoon cream of tartar
Sweet Chocolate Ganache
1 cup heavy whipping cream
8 ounces sweet chocolate, such as germans chopped (but not milk chocolate)
Filling
marshmallow cream

Preparation

Butter and 12x17 jellyroll pan (I used 10x15 and cut back slightly on the ingredients). Line with parchment paper or waxed paper and butter the paper. Beat the egg yolks and sugar until thick. Add the honey, water, oil and butter and mix briefly.
Sift together the flours, baking soda, baking powder and salt. Stir into the butter miture briefly.
Beat the egg whites with cream of tartar until soft peaks form. Beat in the sugar until mixture is firm and glossy. Stir a spoonful of the egg whites into the the batter, then stir them together lightly.
Spoon into the baking pan and spread evenly. Bake at 350 degrees for 15 to 20 minutes until top is golden and center springs back when touched. Cool for 5 minutes.
While cake bakes, make chocolate cream. Put the chocolate in a heatproof bowl. Bring the cream to a near boil and pour over the chocolate. Whisk until melted and combined. Refrigerate, whisking occasionally, until cooled. When ready to frost the cake, beat the mixture until it reaches a spreading consistency. (The mixture is too stiff after about 5 hours in the fridge.)
Spread a clean kitchen towel on a work surface and sprinkle with confectioners' sugar. Invert the cake onto it. Slowly remove parchment.
With a sharp knife, cut a line or groove across the short end of the layer about 1/2 inch from the end nearest you. (The groove lets the cake start start rolling up easily, roll tightly and not crack.) Lift the kitchen towel to start the rolling, then roll up completely. Let it cool for at least 20 minutes and up to a few hours.
Unroll the cake. Spread thickly with marshmallow cream. Roll up and place on a serving platter. Pour ganache over it. Let it set for 30 minutes or so.