Honestly, there are probably 1001 different ways to adapt a bechamel sauce. However, if you're looking for simple ways to add flavor without completely changing the sauce, there are a few options. Add mustard: mustard powder or Dijon mustard are common additions to the bechamel sauce. Add spice: a pinch of chili or cayenne powder is all you need for extra depth of flavor. Onion clouté/pique: pierce a section of onion with cloves (onion cloute) or use the cloves to attach a bay leaf to the onion (onion pique). You can add this to the milk while heating it or into the bechamel – then remove it before using. Onion: alternatively, forget about the above and finely chop and onion. Sauté it lightly until it begins to soften and go translucent - before adding the flour and butter. Alternatively, you could add in a bit of onion powder. Garlic: like the above, you can sauté a little garlic or add a little garlic powder to the sauce.