Preheat oven to (170°C/150°C fan-forced) and grease a 12-hole 5cm mini cheesecake pan (or mini brownie or cake pan).
Melt butter and dark chocolate in small saucepan on low heat until smooth, then set aside to cool for 10 minutes.
Beat eggs and sugars until pale and smooth, then pour in melted chocolate mixture until combined.
Sift together flour, cocoa, baking powder and salt, then add sifted dry ingredients to batter while beating on low speed, until mixture is smooth. Take care not to overmix.
Divide mixture equally between cake pan holes, then place one blackberry into the centre of each brownie. Reserve the remaining 12 blackberries to decorate.
Bake for 17-18 minutes or until cake springs back and a cake tester comes out with moist crumbs. Don’t be tempted to leave the brownies in the oven any longer – they will firm up as they cool and taste much better with a moist centre than being hard and crunchy. Allow to cool 10 minutes in pan, then turn out and cool completely on a wire rack.
Blackberry Cream Cheese Frosting
Blitz blackberries in a food processor, then press through a sieve to achieve a smooth blackberry puree.
Beat butter and cream cheese until smooth and well combined, then add sugar and beat until light and fluffy.
Slowly add blackberry puree slowly until frosting is pale purple and fluffy. You may not need all the puree to achieve the desired texture.
Place frosting in a piping bag fitted with a large round nozzle (10-15mm) for ease when assembling.
Melt chocolate and butter together, then place in a piping bag with the end snipped off (2-3mm hole) for easy drizzling.
Place brownies upside-down on serving plate, then pipe with frosting and chocolate drizzle.
Decorate with 2 meringue kisses and 1 blackberry per brownie, then crush remaining meringue kisses and sprinkle on top for extra texture and aesthetics.