Wash and dry the cucumbers well. Slice them into spears or 1/4-inch thick rounds and place them in a large mixing bowl.
Peel the garlic cloves and gently crush them with the flat side of a knife to release their flavor.
In a small saucepan, combine the white vinegar, water, pickling salt, and sugar. Warm over medium heat, stirring until the salt and sugar dissolve (about 3-5 minutes). Remove it from heat and let it cool slightly.
Layer the cucumbers, dill sprigs, crushed garlic, red pepper flakes, and whole peppercorns in a clean quart-sized glass jar. Include the bay leaves or mustard seeds if desired.
Pour the warm brine over the cucumbers until they’re fully submerged, leaving about 1/2 inch of headspace at the top.
Seal the jar tightly and refrigerate. For the best flavor, let the pickles sit for at least 24 hours before tasting.
Before serving, ensure the cucumbers are submerged in brine. If needed, use a clean utensil to press them down.
Notes
Store in the refrigerator for up to 3 weeks. Use clean utensils to maintain freshness.