1) Take a blazer pan of the chafing dish and place over direct heat.
2) Melt butter in it.
3) Add the flour, mustard and salt, stirring them in.
4) Remove it from the heat.
5) Add the milk slowly, stirring it in.
6) Put the blazer pan on top of hot water.
7) Cook while stirring until the mixture becomes thick.
8) Mix the eggs and ham and blend well.
9) Cook for an additional 5 minutes or until the egg-ham mixture gets heated properly.