A cortado is commonly understood as espresso moderated with a relatively modest amount of warm milk. It is associated with Spanish coffee culture, while the name and preparation also appear in many other café settings. The important contrast with a large latte is the smaller milk contribution rather than a compulsory cup specification.
Ask the café how it serves the drink if size or strength matters to you. Espresso quantity, milk volume and texture can vary, and another business's cortado may not resemble the version you normally order. A short description is more reliable than assuming the menu name settles every detail.
At home, measure the components and compare the balance while the drink remains comfortable to sip. Use milk texture that integrates with the espresso rather than judging the result only by a visible foam layer. Keep the recipe that suits your preference. A useful definition explains the drink without pretending a globally uniform standard exists.

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