Cut chipped beef into small bite-size pieces. Heat 4 Tbs. oil in skillet to medium temperature. Add chipped beef pieces, cook until hot, stirring to break up beef pieces. Stir in flour until a thick paste is formed. Add remaining 2 Tbs oil.
Gradually stir in milk and water. Cook until bubbly. Simmer 5 minutes over low heat. Season with salt and pepper.
Serve hot over toast. Gravy may be thickened by using additional milk, or thinned by using additional water.