Melt butter in pan at medium heat, add oil to prevent burning.

Chop chipped beef fine, and to pan. Sauté 1 min then add garlic crushed and powdered mustard.

Stir 1 minute then add flour, stirring to combine flour and oil. Add sage, worchestershire sauce, then milk a little at a time, stirring to avoid lumps.

Once smooth, bring to boil, turn heat low, then add in shredded cheese. Stir to melt cheese, then turn off heat.

Let sauce think about its sins for 3 minutes (covered, no heat).