Combine the oil, onions and jalapenos in a large stockpot over a high heat. Cook, stirring, until slightly soft, 2 to 3 minutes. Add the garlic, pepper, anchovy fillets, cloves, salt, lemons, corn syrup, cane syrup, vinegar, water and horseradish and bring to a boil. Reduce the heat and simmer uncovered, stirring occasionally, until the mixture barely coats a wooden spoon, about 6 hours. Strain into a clean container.
Worcestershire Sauce may be stored in an airtight container in the refrigerator for up to 1 month, or processed as directed below and kept for up to 1 year.
Sterilize 3 pint-sized jars and their metal lids according to the manufacturer's instructions. Spoon the hot mixture into the jars, filling to within 1/2-inch of the rim. With a clean, damp towel, wipe the rims and fit with a hot lid. Tightly screw on the metal ring. Place, without touching, on a rack in a large, deep canning kettle or stockpot of rapidly boiling water; water should cover the cans by 1 inch. Boil and process for 15 minutes. Using tongs, remove the jars, place on a towel and let cool completely before storing. Test the seals and tighten the rings as needed. Store in a cool, dark place for at least 2 weeks before using. After opening, store jars in the refrigerator.
Yield: generous 3 pints