One of the advantages of quail eggs is they pickle so much faster than chicken eggs. You can buy pre-hard cooked quail eggs in cans at Asian grocery markets. Liquid volumes are approximate. Preparation time does not include marinating time.
Drain the can, and insert a clove into each egg; I am assuming there are approximately 25 eggs in each can. (There may be more.).
In a container, place the eggs, add the other seasonings (including the slice of jalapeno if you wish), and cover with red wine vinegar. Alternatively, make a vinegar to water ratio of 3 or 4 parts to 1 part, if otherwise the taste will be too vinegary for you.
Cover and set in refrigerator for 4 days, or longer. Swirl occasionally.
Drain and serve. Eggs will be pinkish-brown. The swirling will ensure uniform coloration. Depending on your crowd, remove the cloves before serving.