In a sketch with Funny or Die, Zac Efron gets tricked into making his “Dirty Grandpa”; co-star Robert De Niro a sandwich.

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De Niro tells Efron that the purpose of making a sandwich is an acting lesson. But instead of giving Efron advice, De Niro tells Efron to add the necessary parts to a scene, which include two slices of bread, turkey, mayo, mustard and tomato. But don’t forget to add a little bit of cheese.

Watch the full video below.

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