See Under Pressure and Canning Pickles with a Boiling Water Bath for sterilizing and other canning techniques required below.MAKES 1 QUART1 1/4 cup cider vinegar4–5 medium yellow squash, cut into 1/2'' rounds2 tbsp. coarse kosher salt1. Bring vinegar and 1/2 cup water to a boil in a medium saucepan over medium-high heat. Reduce heat to low, cover and keep warm.2. Heat a nonstick skillet over medium-high heat. Working in batches, brown squash in the dry pan until golden, about 2 minutes per side. Transfer squash to a plate, cover, and keep hot.3. With a sterilized fork, layer a few pieces of squash in a hot, sterilized quart canning jar. Scatter some salt over pieces, and repeat layering to fill jar. Add hot vinegar-water to cover, leaving 1'' of headspace from top rim of jar. Place lid on jar and screw on band. Process for 40 minutes at 10 lbs. pressure in a pressure canner. Remove jars from pot and allow to cool, following manufacturer’s instructions. Store in a cool, dark place for at least 3 weeks and up to 1 year.