I love the Subway sandwich with honey mustard sauce but I couldn't get the sauce from the store nearby here. In this case, I tried to mix it on my own and it worked!
Mayonnaise - 2 1/2 tablespoons
Honey - 1 tablespoon
Mustard - 1/4 teaspoon (depends how strong the taste you prefer, I like it mild.)
Mix it well.
My sandwich (picture above) : Turkey breast, tomato, red onion, iceberg lettuce, cucumber with toasted wholemeal bread and Honey Mustard Sauce.
This is my lovely lunch.