Popularly known as the bechamel sauce has a miriad use cases. My personal favorite begins with making Gratin's. Gratins are French dishes that have a vegetables  baked along with bechamel and cheese. This is a simple recipe. You can modify this by adding herbs of your choice.

A few usage ideas:
Vegetable Gratin's - My favorite is the Calulifower Gratin
Sweet corn with green chillies and Bechamel topped on toasted bread. Delicious!