Grease a 23 cm (9 inch) square shallow cake tin. Preheat the oven to 180°C (350°F/Gas 4).
Melt chocolate and butter in a heatproof bowl set over a saucepan of simmering water, or in the microwave. Stir until smooth. In a bowl, beat the eggs, sugar and vanilla. Stir in the chocolate mixture. Combine flour, bicarbonate of soda and salt. Gradually add to the chocolate mixture, then fold in the raspberries. Spoon into the tin, level the top and bake for 25–30 minutes, or until a skewer inserted in the centre comes out clean (do not overcook). Cool in the tin on a wire rack.
For the icing (frosting), in a small microwave-safe bowl, microwave the chocolate, cream and jam at 50 per cent power for 2–3 minutes, or until smooth, stirring twice. Stir in the vanilla. Place the bowl in a bowl of iced water, stir for 3–5 minutes, then beat on medium speed until soft peaks form.
Fill a piping (icing) bag fitted with a star tip with ½ cup (60 g) of the icing. Spread the remaining icing over the top of the brownies. Cut into 12 bars. Pipe a chocolate rosette in the centre of each brownie. Top with a raspberry and mint leaves. Cover and refrigerate for 30 minutes, or until the icing is set. Store in the refrigerator.