Place Serrano peppers in a colander and rinse them under warm water, using your fingers to gently rub away any dirt or residue.

Safety Note: Wear gloves throughout this process to protect your skin and eyes from the peppers’ capsaicin.

Cut the tops off each Serrano and shake out the seeds.

Halve each pepper and scrape out any remaining seeds, then dice the peppers until you have 1½ cups of chopped product.

Combine 2 tablespoons of pickling spices (such as mustard seeds, allspice berries, whole cloves, dill seeds, and peppercorns) in a small square of cheesecloth.

Tie the cheesecloth securely with string to form a spice bag that will infuse your sauce without leaving loose seeds.

In a stainless steel saucepan, combine the 64-ounce can of undrained tomatoes, the prepared Serrano peppers, and the spice bag.

Add 4 cups white vinegar and 2 teaspoons canning salt.

Bring the mixture to a boil over medium-high heat, then reduce the heat and simmer for 20 minutes, stirring occasionally. The tomatoes and peppers should become very soft and the flavors meld.

Remove the spice bag from the pan and discard it.

Pass the remaining mixture through a food mill to separate the liquid from the seeds and skins. Discard the solids trapped in the mill.

Return the strained sauce to the stainless steel saucepan and heat over medium.

Bring the sauce to a boil and continue cooking for an additional 15 minutes, uncovered, to allow excess liquid to evaporate and the sauce to thicken.

Inspect seven half-pint jars for any chips or cracks, then wash them in hot, soapy water.

Place the clean jars in your water bath canner, fill with water, cover with the lid, and heat over medium until needed.

Warm the lids in a small saucepan with warm water over low heat.

When the sauce has thickened, remove the saucepan from the heat.

Using a jar lifter, remove the jars from the canner and place them on a towel or cutting board.

Insert a canning funnel into each jar and ladle the hot sauce into the jars, leaving at least ¼ inch of headspace for expansion.

Wipe the rims of the jars with a damp paper towel to remove any splattered sauce.

Use the lid lifter to remove the warmed lids and place one on each jar. Secure the lids with rings, tightening until finger-tight—tight enough to hold the lid in place yet allowing air to escape.

Carefully lower the filled jars into the water bath canner, ensuring they are covered with at least one inch of boiling water.

Cover the canner with its lid and process the jars for 10 minutes, adjusting for your elevation if necessary.

After processing, turn off the heat and remove the canner lid.

Let the jars remain in the canner for 5 minutes to stabilize, then use the jar lifter to remove them and place them on a towel or cutting board.

Allow the jars to cool undisturbed for 24 hours.

After 24 hours, remove the rings from each jar and press the center of each lid with your finger.

If the lids do not flex or pop, the jars are properly sealed.

Label each jar with the date. If any jar fails to seal, refrigerate it and consume the contents within a few days (or freeze if preferred).