The French 75 was highly advanced for its time: lightweight, accurate, manoeuvrable and deadly. So — apparently — is the field gun after which they named it. Essentially it’s a Gimlet topped up with fizz. Were it a Gimlet topped up with soda it’d be a Tom Collins, but this is more fun, and more dangerous. You could serve it with ice in a Collins glass, but I think a flute looks classier, and if your champers is chilled you won’t need ice.
Start with 25mL gin, 12.5mL lemon juice, and 5mL sugar syrup. Stir firmly with plenty of ice, and then strain into a flute. Top with 125mL or so of bubbles. I’ve garnished mine with a twist, but don’t feel obliged. Down the hatch and vive la république!
A single shot of gin might sound parsimonious, and if you slip very slightly, then it won’t hurt and you’ll end up with a friskier drink. Some recipes call for double measures and less champagne, but I don’t think it’s as nice. Feel free to swap the champers for prosecco or cava, but don’t tell the French.
Dried Basil and Other Heresies 
I can tell how you have been passing the time under lockdown.:) And it sounds like fun! Maybe we’ll make it over that way sometime in the future when air travel resumes.If we aren’t reduced to the level of impoverished peasants by the economic meltdown.