Soubise is an onion béchamel which makes the perfect accompaniment to lamb. Classically the sauce is made in three stages, with the onion first blanched in boiling water, before being sweated in butter then added to a béchamel and simmered for 15 minutes. It is then sieved and has double cream added. The process can be simplified as below.
Sweat the onion in the butter until soft and translucent, but don’t allow it to brown. Stir in the flour and cook to a roux for 2 minutes.
Pour in the milk and simmer, stirring occasionally, for 20–30 minutes, when it should be thick and creamy and reduced to about
Purée in a food processor or blender. Pour back into a clean saucepan, taste and adjust the seasoning if necessary. You can add a few tablespoons of cream if you like.
Reheat gently before serving.
© 1998 Alastair Little and Richard Whittington estate. All rights reserved.