Adapted from Tart and Sweet:

Yield: 4 half pints

Some amount of garlic scapes, cut ends trimmed (I have no idea how many garlic scapes yielded this - it was about a medium-sized bowl full, not packed tightly; maybe 2 pounds?)

1.5 cups apple cider vinegar
1/2 cup water
1 Tbsp kosher salt

Per half-pint jar:
1/2 Tbsp minced shallots
1 bay leaf
2 teaspoons brown mustard seed
1/2 tsp black peppercorns

Bring vinegar solution to a boil. Pack scapes into hot jars in a coil shape. Put rest of spices in middle where there will inevitably be a hole. Ladle hot brine into jars. Good luck getting the lids on with 1/2" headspace.

Process for 10 minutes.