Preheat the oven to 170C/325F/Gas 3.
Line a 23cm/9in square cake tin or a roasting tin 20x25cm/8in x 10in with baking parchment.
Melt the chocolate and butter together in a glass bowl over boiling water ensuring that the water level is always below the base of the bowl and then allow cool slightly.
Next whisk the eggs until thick, gradually add the sugar and beating until glossy. Add the melted chocolate mixture gently folding in the flour, baking powder and salt.
Pour just over half the mixture into the prepared cake tin and scatter over the raspberries. Finish by adding the remaining mixture.
Bake in the centre of the preheated oven for about 30 minutes or until the surface is set. A skewer is inserted into the middle should come out with just a little mixture sticking to it. Allow to cool for 20 minutes before lifting the brownies from the tin using the edges of the baking parchment and place on a wire rack and only remove the paper when completely cold. Then cut the cake into squares.
Serve as a dessert, if desired, with crème fraiche and some extra raspberries.
For a change, try spooning a 397g tin of Carnation Caramel with a pinch of salt flakes over half the mixture before adding the rest. Draw a skewer through the mixture to ensure the caramel is well distributed.
Alternatively, add 150g chopped walnuts instead of raspberries for a chocolate and nut brownie.
Iain Watters has provided this recipe to support Wallace & Gromit's BIG Bake
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