I am an avid tea drinker but I am not really a fan of green tea. Yet one day, I was again lost in the world of recipes on the internet, getting excited with many things to try, and then I saw this ingredient: green tea powder, which you can use to make cakes, cookies, pastries… That was it – I had to try green tea powder!
So I started searching where you could find this in Helsinki. By now I know my way around Helsinki when it comes to searching for an ingredient, therefore the first place I checked had it of course: Ruohonjuuri. As many other things in Ruohonjuuri, it was quite expensive. But since you use only a small amount of it in recipes, I thought it could be an acceptable investment, because I could use it in several different dishes. And yes so I did. I made bread, cookie, panna cotta (which was a rather disaster because of the horrible ingredient called “gelatine”, hrrr…) and this cake.
Green tea powder adds a hint of tea taste in the food, and it makes it taste somehow more fresh. It is rather an acquired taste, so if you are especially in favour of more traditional tastes, I have to warn you that the first few times you eat something with this might not really satisfy you. But be patient, you will eventually enjoy it.
This is actually just a regular swiss roll cake. The only difference is the addition of green tea powder towards the last steps. So you can definitely use this recipe to make a more traditional swiss roll cake without green tea. You can also just substitute green tea powder with cacao or chocolate and make a chocolate swiss roll. You can even change the filling and make another version – I just happened to have raspberry jam at home and made raspberry buttercream but you can try it with cranberry buttercream or regular cranberry cream as well. Cranberry and green tea work really good (tested and approved!). I actually do hope that you make your own twist and then write to me about it!
Enjoy your green tea experience!
For sponge cake:
1 egg yolk
1/3 cup / 78 ml cake flour
3 tbsp / 45 ml cornstarch
1/2 cup plus 1 tbsp / 120 + 15 ml granulated white sugar (divided)
1 tsp / 5 ml vanilla extract
1/4 tsp / 1.25 ml cream of tartar (optional, you can find it in Behnford’s in Helsinki City Center)
2 tsp / 10 ml Matcha green tea powder (you can find it in Ruohonjuuri, the Keiko brand is 12.95 euros for 50 gr. package)
For buttercream filling:
1/4 cup / 56 gr. butter (in room temperature)
1/2 cup / 120 ml raspberry jam (the jam I used was quite sweet so I didn’t add any extra sugar. But if it does not feel so sweet for you, you can also add 1/2 cup / 120 ml. granulated white sugar)
If you want to use fresh raspberries, you can use the buttercream recipe in my French macarons post: https://mydearkitcheninhelsinki.wordpress.com/2013/10/31/french-macarons-the-ultimate-baking-challenge/
1. Preheat the oven to 230C.
Preparing the sponge cake:
2. In a bowl, put flour and cornstarch and just give it a brief mix with a spoon.
3. Separate 4 egg yolks from whites, keep the whites for later use. Add 1 more egg yolk to the 4 yolks, and put them in a mixing bowl. Add 1/2 cup /120 ml sugar and using a hand or stand-in mixer (or with a hand whisk, if you have enough strength), mix them until it is white and smooth. This takes about 10 minutes in medium slow mixer.
4. To this now white-ish mixture, add vanilla extract and mix it just until vanilla extract is incorporated.
7. In the mixing bowl, put 4 egg whites that you kept in step 3 and beat it until it is white and foamy. Add cream of tartar (if you are using) and 1 tbsp / 15 ml sugar and keep beating until it gets creamy and smooth.
8. Add this white creamy mixture to the green tea-flour mixture and just fold until the ingredients are all incorporated and you have a smooth cake batter.
9. Put a baking sheet on a flat oven tray. Pour the batter onto the baking sheet and tap it a few times on the counter to get the air bubbles out.
10. Put the batter in the oven, in middle rack. Bake for about 6-8 minutes, until just browned a little. Then take it out of the oven. The cake should spring back when you press it (hence the name “sponge cake”).
11. Let the cake cool down a bit. When it does, take it away from the baking sheet and cut it in a rectangle shape. Put aside while you are preparing the filling.
Preparing the buttercream filling:
12. Cut the butter into small cubes for easier handling. Whisk it a little to smooth out. Add raspberry jam and using a mixer or a hand whisk, mix them together until fully incorporated and creamy.
13. Spread the buttercream evenly on the sponge cake. One surface of mine was a bit too browned so I used that surface to spread the butter since it would stay inside.
14. Roll the cake as the filling surface would stay inside, from the shorter edge, alongside the longer edge. Cover it with a baking sheet to keep its shape and put it inside the fridge for at least 2 hours.
15. After chilling the cake for at least 2 hours, take it out and cut it in size you like. Keep the remaining cake in the fridge, not in room temperature.
MMMMmmm…. creamy… and green!