Line a 14x21-cm loaf pan with a strip of foil or baking paper to cover the base and extend over the two long sides.
For the parfait, blend or process the ricotta and sugar until smooth. Beat the cream in a small bowl with an electric mixer until soft peaks form. Combine the ricotta mixture, nuts and nougat in a large bowl; fold in the cream, then the raspberries.
Spoon the mixture into the prepared pan, cover with foil and freeze for 6 hours or until firm.
Meanwhile, make the berry compote: combine the raspberries and sugar in a medium pan and cook, stirring, over a low heat, until the berries are very soft. Push the raspberry mixture through a sieve into a bowl; discard seeds. Just before serving, combine the raspberry puree and the rest of the berries in a medium bowl.
Slice the parfait, then refrigerate for about 30 minutes before serving to allow it to soften slightly. Serve with berry compote.