Pre-heat oven to 180°C (160°C fan-forced). Line a 25-27 cm loaf tin with baking paper. (You can use any size tin as long as it will hold at least 1.6 litres in volume.)
Place prawns in food processor and process until pureed. Add eggs and process till combined. With motor running slowly add cream, then season.
Pour into prepared tin. Bake for 40 minutes or until set.
Meanwhile for basil mayo: place egg yolks and mustard in the bowl of a food processor and process until pale and thickened. Combine oils and drizzle in slowly while continuing to process. The slower you do it, the thicker your mayo will be. Season with lemon juice and salt. Pulse through the chopped basil. Refrigerate until ready to use.
Remove loaf to cool slightly, then turn out, cut into slices and serve with basil mayo and salad, if desired.
