Love the pretty rainbow stripes!
I had more than enough batter so I let the kids mess around with their psychedelic rainbow Swiss roll!
I used Ochikeron's recipe and method to make this Swiss roll with minor modifications.
Egg yolk batter
1 egg yolk (63-65g eggs)
33g caster sugar
20ml + 25ml canola oil
1/2 tsp vanilla extract
80g cake flour
Red, yellow, green, blue and purple gel food coloring
4 egg whites
30g caster sugar
1/4 tsp cream of tartar
2 tsp caster sugar
4 tsp hot water
1 tsp strawberry essence
150ml Whip topping (You may replace with dairy cream which tastes better. But if you do, add 1.5 tbs of icing sugar when you whip.)
1 tsp gelatin powder
1 tbs water
Some strawberries and/or other fruits of your choice, sliced to small pieces
1. Line the bottom of a 10 x 10" pan and 6 x 6" pan (optional) with baking sheet or silicone baking mat. Lightly grease the baking sheet or silicone mat. **(Silicone mat would be better if you can get one as it prevents wrinkles from forming on the surface of your swiss roll. You can see from the psychedelic swiss roll that there is a bit of wrinkling as I used baking sheet for that one and there is no wrinkling for the striped swiss roll as I used a silicone mat.) Prepare 5 piping bags with 1cm round tip attached or simply use the piping tip adapters without tips attached like I did. I only have 5 piping tip adapters of the same size at home and hence only 5 colors for the rainbow. You may choose to just cut a hole in the piping bag but that will not produce the neat, regular stripe pattern that you see on my swiss roll. Preheat the oven to 160 degrees Celsius.
2. In a bowl, place egg yolk, sugar and 20 ml oil. Beat them with electric mixer until white. Add water, 25ml oil and vanilla extract and mix well. Sift in cake flour and mix until the consistency of the batter is like gruel. The cake won't crack so easily this way. Divide the batter into 5 equal portions and color with food coloring until desired shade is reached.
3. Prepare the meringue. In a clean metal bowl, beat egg whites until foamy. Add cream of tartar and beat until soft peaks form. Gradually add sugar until stiff peaks form. Gently but quickly fold in the meringue into the 5 egg yolk batters in 3 batches.
4. Transfer the colored batter into piping bags and carefully pipe diagonal stripes, trying your best to keep the width of the stripes regular. Start by piping a triangle from one corner.
I had some left over batter so I let the kids mess around with it for a small roll.
5. Bake for 14 minutes. Cut the cake around the edges to release it from the pan and turn it out onto a cooling rack.
6. Roll the cake while it is still warm to cool, with baking sheet covering it. This will prevent it from cracking when you roll it later with the filling.
7. Prepare the syrup by dissolving sugar in hot water and adding strawberry essence.
8. Prepare the cream. Sprinkle gelatin over 1 tbs of water and let it bloom (sit and absorb water) for 1-2 minutes. Microwave on medium-high heat for 20 seconds or until gelatin dissolves. Warm up 1.5 tbs of Whip topping and mix well with gelatin mixture. Set aside. Use an electric mixer to beat the Whip topping until firm peaks form. Gradually add the gelatin mixture and continue whipping until well incorporated.
9. Unroll the cakes and brush some syrup on the surface. Apply the cream on top, leaving one inch without cream at the top. Line some strawberries. **(It is not necessary to make horizontal cuts on the cake as this rainbow roll is quite thin and I have rolled the cake while it was still warm. A foolproof way to prevent swiss rolls from cracking!)
10. Roll up the cake carefully with baking sheet and twist the ends. Refrigerate for at least 2 hours.
11. Cut the ends of the swiss roll, reshape it and refrigerate again for at least an hour. Remember to use a hot serrated knife to cut the swiss roll and clean the blade after each cut.
Here's a collage of my kids piping the batter, applying syrup and cream, and loading their roll with lots of fruits! Last pic is of them eating the leftover fruits after the roll was done :P.
All packed and ready to be presented!
A close up view of a slice!
Phay Shing & the kids