Grate the cheese and garlic on a fine grater.
Break chicken eggs into a tall measuring cup.
Beat the chicken eggs slightly until smooth.
Gradually pour in vegetable oil in a thin stream and continue to beat the mixture with a blender. Before your eyes, the oil and eggs will begin to turn into a thick emulsion.
Add grated cheese, tuna, garlic, Dijon mustard, sugar, salt and black pepper to the sauce.
Blend the sauce until smooth.
The roast beef sauce is ready.