Put the buttermilk and sugar in a saucepan and bring to a boil. Always stir well with a whisk in between. After about 1/2 hour the mass will slowly become thicker. At some point the mass gets the typical honey color. After about 3/4 to 1 hour the mass is viscous. Now you can transfer them to a jar, Tupperware box or a honey jar. After cooling down, you can enjoy this wonderful homemade milk honey.
This is a very old recipe - dating back to the pre-war years. I got it from my dear godmother.