Put the cucumbers in a big bowl and pour the pickling salt over them. Cover with 3 cups of ice and set aside for about 4 hours to make its own brine. Drain and rinse well.
Put the jars into the dishwasher on a rinse cycle and put the lids into simmering water so that they are clean and hot when you start filling the jars.
Fill a stockpot or canner with enough water to cover the jars by 2 inches and bring the water to a boil.
In a 5- to 6-quart heavy pot, bring cucumbers, onions, 1 cup water, vinegar, sugar, spices and serrano peppers to a boil. Boil 5 to 10 minutes after boiling starts.
Place 3-5 rings of red jalapeño into the bottom of each jar.
Carefully ladle the hot mixture into hot jars leaving 1/2-inch space on top.
Wipe the rims and sides of jars before using tongs to top with a hot lid.
Screw the lids on firmly and place jars into canner and boil for 10 minutes.
Remove jars using tongs and place on a towel-lined jelly roll pan or countertop to cool.
Over the next 12-24 hours you’ll hear a “ping” as the lids go concave signaling a secure seal. If the lids do not go concave, refrigerate the jar and use it first.
Store securely sealed jars in a cool, dark place for up to a year.