The espresso romano is a simple yet intriguing beverage. In its purest form, it is an espresso served with a slice of lemon, even though its preparation may differ from café to café

https://perfectdailygrind.com/2021/01/what-is-the-espresso-romano/

So, what’s the deal with the espresso Romano? It’s quite simple, really. A proper shot infused with the sweet and citrusy flavors of lemon. Here’s where things get complicated: Some people will use orange wheels or wedges, while others will only use the yellow fruit’s peel.

https://www.perfectbrew.com/blog/espresso-romano-easy-coffee-recipe/