Combine clementine juice, rice vinegar, sugar, jalapeño and butter in a medium-large saucepan (at least 6-quart size). Stir and bring to a boil. Reduce to a steady simmer and cook for 10 minutes. Watch carefully to keep the mixture from boiling up over the top of the pot.
Add Certo pectin and stir constantly for exactly one minute. Remove from heat and skim off any foam with a metal teaspoon. Remove jalapeno and add one teaspoon Chili Garlic Sauce. Taste (be careful, it's hot!) and add more, to taste. Ladle into clean jars, leaving ½ inch headspace at the top. Cover jars and allow to sit at room temperature for 24 hours then refrigerate for up to 3 weeks or store in the freezer for up to 6 months. Makes about 4½ cups of jelly or 9 4-ounce jars.
See Café Tips above in post for lots of additional information and specific tips for making this recipe.