Add the cucumbers, dill, garlic and bay leaf to a large (about 1 quart or 1 liter) jar, layering the dill and garlic between the cucumbers if possible.
In a measuring jar, briefly whisk together the water, vinegar, salt, peppercorns and crushed red pepper flakes until combined.
Pour the brine over the cucumber mixture. Then cover the jar securely with a lid and give it a good shake to combine. If needed, press the cucumbers down so that they are more or less fully submerged.
Refrigerate. Refrigerate for ideally at least 1 day before eating, although the pickles will be lightly brined and ready to enjoy after just a few hours if you would like. Pickles can be stored in a sealed jar in the refrigerator for 1 week.*
