The Limoncello Negroni is pretty good, but limoncello is yellow and we wanted a yellow Limoncello Negroni, so we created a variant of the Negroni Bianco, which replaces the white vermouth with limoncello.
Half-fill a mixing jug with ice.
Add all ingredients and stir until well-chilled.
Strain into a tumbler over fresh ice.
Garnish with a lemon wheel.