Continuing with our way through the 24 Days of Cookies calendar, we tackled this lime bar. Unlike most Key lime bar recipes, this one doesn’t use any condensed milk at all, but does use mint in the crust.
The recipe is a two-parter. We started by making the shortbread crust, which is greatly improved over plain cookie bases, by the addition of lime zest (massaged into the sugar until it turns pale green) and finely chopped mint.
For the curd, lime and lemon juices are combined in a 3:1 ratio, then the recipe proceeds as most other citrus curds go, using five egg yolks and a whole egg to thicken, plus a bit of cornstarch. The directions don’t say, but I poured the hot filling through a sieve to ensure I caught all the cooked egg bits and chalazae.
During baking, the edges boiled, and looked really runny and translucent by the time the centre was set. I’m not sure if that was the baking spray I used on the pan, or just the heat from the metal sides. After cooling and chilling, however, the edges were as firm as the rest of the curd. As promised, this bar slices very cleanly when it’s cold.
The taste is what sets this lime bar apart from others. The curd is very sharp, making your mouth water with every bite. I would almost describe it as juicy. But the crust is where the surprise is: the lime and mint flavours are quite prominent, even after baking. Highly recommended.