<p>1. For the sauce: melt the butter in a pan over a medium heat, whisk in the flour and cook for 2 minutes. whisk in the milk, simmer until bubbling, add seasoning to taste&nbsp;</p><p>2.Divide the prawns and scallops equally between shells and pour sauce over them, leave to cool.</p><p>3.Steam the potatoes until soft ready to mash with a potatoes ricer, mix in butter, egg yolks and season to taste and put in piping bag.</p><p>4.Pre- heat the oven to 190C. Pipe the mash on top of the shell and place in the oven for 8 minutes&nbsp;</p><p><br></p><p>Garnish idea: Parmesan crips, focaccia&nbsp;</p>