This was good, if a bit acidic-- I might tone down the lemon a bit. Maybe we were a bit too aggressive with the muddling, or our lemon was a bit bigger than advertized. That is the problem with specifying fruits by the piece, rather than Tablespoons of juice or somesuch-- a recipe that calls for one onion won't be thrown off, but too much acid really messes up a drink balance.
Next time, we will use measured lemon juice, maybe with the proportions of a sidecar, and add the lemon oils by muddling a little of the peel, or maybe garnishing with a flamed peel. Once the balance is correct, this will be a great summer drink-- I could see topping it off with a big splash of soda water, or maybe a dash of Campari. Okay, I am officially ready for summer.