Prepare the Cucumbers: Wash the cucumbers thoroughly and slice them into spears or chips. Set them aside.
Make the Brine: In a large pot, combine the sugar, vinegar, mustard seeds, dill seeds, allspice, garlic, and pickling salt. Heat the mixture over medium heat, stirring until the sugar dissolves completely. Bring to a boil, then remove from heat.
Add the Cucumbers: Carefully pack the cucumber slices into sterilized glass jars, leaving a little space at the top. If using, add the optional peppers and herbs to the jars for extra flavor.
Pour the Brine: Pour the hot brine mixture over the cucumbers, ensuring they are fully submerged. Use a spoon to gently press the cucumbers down and release any trapped air bubbles.
Seal and Cool: Seal the jars tightly with lids and allow them to cool to room temperature. Once cooled, refrigerate the jars for at least 24 hours to allow the flavors to develop. For the best flavor, let the pickles sit for a week before enjoying.