Preheat oven to 350. Spray a 15 10 by 1 inch jelly roll pan with non stick spray. Line pan with parchment paper and spray paper with non stick spray
Have egg whites in one large bowl and egg yolks in another large bowl and have them at room temperature
Whisk flour. baking powder and salt in a bowl, set aside
Beat egg yolks and buttermilk until light in color and increased in volume. Beat in 1 cup of the sugar and vanilla until well mixed
Stir in flour mixture. Making sure it's mixed well but don't overmix
With clean and dry beaters beat egg whites and cream of tarter until soft peaks form, slowly add remaing 1/2 cup sugar and beat until glossy peaks form
Fold 1/4 of egg whites into egg yolk mixture then fold in remaining in 3 more additions.
Spread batter evenly in prepared pan.Bake 16 to 18 minutes until golden and not sticky to touch and it springs back when touched
Cool 5 minutes on rack in pan. Run a knife around edges of cake to unstick any edges if cake
After cake cools 5 minutes invert onto confectioners sugar dusted kitchen towel. Carefully peel off parchment paper
Roll cake up in towel, into a roll. Cool in towel on rack
MAKE FILLING
Beat cream until soft peaks form, add strawberry jan, confectioner's sugar and vanilla and beat until stiff peaks form. Add drops of food color now if you want a darker pink color.
Unroll cooled cake and spread strawberry cream over cake
Roll cake up, using towel as a guide to tightly roll. Place seam side down on pan and frost withe Creamy Buttcream Frosting recipe attached below, and decorate with sprinkles, strawberries and blueberries. Cake should be stored in refigerator
https://cookpad.com/us/recipes/367337-basic-creamy-vanilla-buttercream-frosting
