In India, where the love for pickles runs deep, some varieties, such as mango, are consumed nationwide, and others are region-specific, such as kohlrabi, which is specific to Kashmir. Some regional pickles deserve wider exposure; the kohlrabi pickle is undoubtedly one of them. Let me do my bit in this post, including sharing a recipe.
Kohlrabi is a vegetable with a round, light-green colored fleshy bulb, and a dark-green leafy top. The bulb is crunchy 
and mildly sweet. Although people in many parts of India eat kohlrabi, I have never seen it served at a restaurant, a college dining hall, or someone’s home, sold at a vegetable vendor, or mentioned in conversation outside of Kashmir in India.
In Kashmir, kohlrabi is king! Almost. It’s the second most consumed vegetable. The first is collard greens, called haakh in Kashmiri. Kohlrabi is called monje haakh; monje denotes the bulb, and haakh refers to the green leafy top—it resembles collard greens in appearance and taste (read about Kashmiri cuisine here and collard greens here).
Interestingly, while Kashmiris love kohlrabi, in part given its similarity to their favorite collard greens, African Americans, heavy consumers of collard greens in the United States, are not into kohlrabi.
American supermarkets typically offer kohlrabi with the greens intact, whereas Indian and Chinese grocery stores in the United States sell it without the greens, probably because they are hard to store and have a short shelf life. However, my Chinese American friend tells me kohlrabi greens are more suitable for cattle feed. That is at odds with the diversity and ingenuity of Chinese culinary traditions.
Most Americans also don’t eat kohlrabi greens. Well, the Kashmiris do and cook the chopped greens with slices of the bulb. They use the greens for pickles as well.
Kohlrabi belongs to the cabbage family, which hails two renowned pickles, German sauerkraut and Korean kimchi. The mild taste and optimal water content of kohlrabi are perfect for absorbing spice flavors and make it ideal for an Indian pickle. The bulb provides crunchiness, and the greens offer chewiness.
Let’s start with the recipe for you to savor this exotic pickle. My recipe is from the Hindu tradition of Kashmiri cuisine, which eschews onions, garlic, and tomatoes.
A dish is only as good as the quality of its ingredients. Do not make this pickle if you can’t get fresh and tender kohlrabi. Kohlrabi, when overmatured, becomes fibrous, tough, and woody.
Kohlrabi pickle (monje haakh achaar)
Recipe Ingredients
6 pounds of kohlrabi bulbs with greens
¼ teaspoon asafetida
2 tablespoons coriander seed
1 teaspoon carom seeds
2 tablespoons black mustard seeds
2 tablespoons salt
5 tablespoons Kashmiri red chili powder
1 to 2 cups mustard oil
Instructions
1. Thoroughly wash kohlrabi.
2. Pluck the greens from the bulbs, discarding stems. Chop greens into bite-size pieces.
3. Remove the hard bottom and tough ridges from the skin.
4. Cut the bulbs into half-inch cubes.
5. Dry the cubes and greens indoors; the leaves turn yellow quickly in the sun. 
6. We want to dry the cubes on the outside but not dehydrate them.
7. Lightly roast the coriander, mustard seeds, and carom seeds. Let cool. Coarsely grind the roasted seeds.
8. Mix the coarsely ground seeds, salt, asafetida, Kashmiri red chili powder, and mustard oil in a large bowl.
9. Thoroughly coat cubes and leaves with the oil mixture and pour into a clean, dry, airtight glass jar. Each and every piece of bulb and leaf should be coated.
10. Let the jar sit for four/five days, and refrigerate once the tanginess of the pickle reaches the desired level. 
Adaptation
You can adjust ingredient quantities based on intuition and preferences. Here are some insights into the ingredients to help guide your customization.
Oil
Function: binds spices, facilitates absorption of flavors, forms a protective layer
Choice: raw mustard oil has a distinctive flavor and serves as a preservative due to its antimicrobial properties.
Variation: to eliminate harmful microorganisms and pungency, some use smoked and cooled oil
Mustard Seeds
Types: black ones offer the most intense flavor
Contribution: flavor and a mild crunch
Tip: crushing seeds is critical to releasing their full flavor
Coriander and Carom Seeds
Function: add flavor and aroma
Additional Benefit: Carom seeds bring digestive properties to the mix.
Salt
Role: preservative and fermenting agent
Tip: use non-iodized salt
Over to You
Kohlrabi pickle is straightforward to make. Go for it! Enjoy it with rice. Warning: resist the temptation to use it as a main course. It’s a condiment.
bon appétit
NOTES
Kohlrabi is typically green, but there is also a deep-purple variety. 
The top part of the bulb, along with some tender greens attached, is cut as one piece. This is the prized part of the vegetable dish when it’s cooked. I used these cuts in my pickle.
If you don’t like the intense flavor of mustard oil, smoke it to mellow its pungency. But smoked oil is unhealthy because, at the smoking point, the oil molecules degrade to bad stuff. Maybe heat it just below the smoking point.
In the United States, you can buy mustard oil in Indian grocery stores. In compliance with FDA regulations, mustard oil sold in the United States is labeled “for external use only.” The Erucic acid in mustard oil is considered harmful to cardiovascular health; the evidence is sketchy. Millions of South Asian households use mustard oil as a cooking medium every day.
Don’t substitute regular red chili powder for Kashmiri red chili powder. Kashmiri chili powder is much milder and imparts a deep red color.