In an electric mixer on high speed, cream butter and sugar until mixture turns from yellow to off-white (between 5 and 20 minutes, depending on softness of butter).
Add eggs, one at a time, beating between additions. Do not allow mixture to split.
Sift flour and baking powder together and, in a separate bowl, combine milk and vanilla bean paste.
Add half the flour mixture, half the milk mixture and half the sour cream to the butter mixture. Mix well, then add remaining flour mixture, milk mixture and sour cream. Fold in pistachios and cardamom powder.
Spoon mixture into mini cupcake foils, about 20g each.
Bake for 30 minutes, turning tray around once at 15 minutes.
Whip the butter until pale and creamy. Add icing sugar and
beat on high speed for a further 5–10 minutes. Add egg whites, lemon juice and vanilla bean extract.
Cream for an additional 3 minutes.
Spread over cooked cupcakes.
Notes & Tips
Recipe taken from the book "Sparkle Cupcakes: The Little Black Book" by Kathryn Sutton, 2011
RRP $29.95 www.newholland.com.au