Béchamel (or White) Sauce
1 onion, halved
1 bay leaf
50g plain flour
Gently bring 500ml milk to the boil in a small saucepan with 1 halved onion, with 1 bay leaf. Turn off the heat and leave to infuse for 20 mins.
Melt 50g butter in another saucepan, then add 50g plain flour. Stir continuously until a paste forms. Continue cooking for 2 mins.
Remove the onion, bay and cloves from the milk with a slotted spoon and discard. Add the infused milk gradually, stirring as you go, until you get a smooth sauce. Cook for 5-10 mins, stirring continuously, until the sauce has thickened. Season to taste.