Okay, this relish is actually a bit different from the bread-and-butter pickles you may know from childhood. It's also much simpler. It does have a similar flavor profile, though: sweet and bright, with warm spices.
It's a quick pickle in every sense, just a thirty-minute bath in the vinegar before it's ready to serve, and I simply keep it in the refrigerator for up to two weeks, rather than canning it. It never lasts long enough to put up, anyway. Serve as a side salad, or on sandwiches and burgers, or chop up and mix into potato salad.
Apple Notes: Red-skinned apples look prettiest here, I often use Jazz, Baldwin, and Melrose here.
Note: To make this pickle truly pretty (and easy), the mandoline and biscuit cutter are essential. The mandoline because you want paper-thin slices, and the biscuit cutter so you can create apple slices that are the same size as the cukes. You don't need anything fancy, though.
1. First, prep your cucumbers: Cut off the ends and discard, then slice on a mandoline. Put in a colander and toss with the salt. Let sit for at least 20 minutes.
2. Meanwhile, prep the apples: Trim the seeds and core from each apple half, then set, cut-side down, on a cutting board. Use a biscuit cutter to push down into the flesh, extracting two little cylinders from each apple half. Because the apples are round, the cylinders won't be perfectly level. That's fine. Thinly slice each cylinder on the mandoline (again, don't worry if some slices are not perfect circles). Slice the shallots on the mandoline as well, then put in a medium bowl with the apples.
3. In a small bowl, whisk together the vinegar, water, honey, and sugar until the sugar dissolves. Add the cinnamon stick and tarragon, and pour the mixture over the apples and shallots.
4. Rinse the cucumbers well and lightly blot dry (still in the colander) with paper towels. Add the cucumber slices to the bowl with the apples and stir well. Let sit for at least 30 minutes before serving. Refrigerate for up to two weeks.