How to Use Black Garlic (And Three Products Worth Buying)

I ate this at Bar Centraal in Amsterdam and filed it away immediately. Radish tempura with black garlic aioli. Not complicated, just creative, and very good. I've recreated it here from memory.

Before the recipe though, everything you need to know about the key ingredient.

What is black garlic?

Black garlic originated in Korea, where it has been used for centuries both as a food and for its health properties. It's made by holding whole bulbs of garlic at a consistent low heat and high humidity for several weeks. The Maillard reaction does most of the work, breaking down the sugars and transforming the cloves until all the sharpness disappears. What's left is molasses-dark, subtly funky and savoury, closer to tamarind or balsamic than anything sharp. No bite, no raw heat.

If you've ever loved roasted garlic, black garlic is the next step. The same sweetness and mellowness, but more concentrated and complex, with a soft almost jammy texture that dissolves easily when mashed or blended. The curing process also increases its antioxidant concentration significantly compared to raw garlic, making it one of those rare ingredients that's as good for you as it tastes.

It shows up as a secret ingredient in more products than you'd think, precisely because it adds background umami depth without tasting obviously of garlic.

How to use it

Black garlic doesn't need cooking. You can use the cloves straight from the jar in dressings, aioli and marinades. The flavour is already fully developed. It's more concentrated than regular garlic, so start with less than you think you need and adjust from there. Once opened, store in the fridge and use within a few weeks.

Three products, three ways in

Black Garlic Peeled Cloves are the purest, most direct format. Blend into dressings, aioli and marinades, mash into butter or hummus, tuck into a braise or stir into a sauce. Because it's just the cloves with nothing added, the flavour is clean and concentrated and you're in full control. This is the version used in the aioli recipe below.

Hawkshead Relish Black Garlic Pickle is something else entirely. The black garlic cloves are slow-cooked for 45 days until meltingly soft, then combined with dates, onions, coriander, ginger, chilli, cumin and lime. The result is a layered, complex relish with balsamic depth, gentle heat and a sweet-savoury richness that goes well beyond any single ingredient. Handmade in the Lake District by a family-run producer, still made in open pans in small batches without additives. A Great Taste 3-star winner in 2018, which is genuinely hard to earn. Use it on a cheese or charcuterie board, alongside roast meats or aged cheeses, in sandwiches with sharp cheddar or cold roast beef, or stir a spoonful into a savoury pie or braise. It also makes a brilliant substitution in the aioli below, sweeter and more complex than the cloves alone.

Silver & Green Organic Black Garlic Oil is Spanish organic extra virgin olive oil infused with black garlic, balanced so the garlic flavour is present but not dominant. It's the format to reach for when you want a milder, more subtle hit. Drizzle over roasted vegetables, grain bowls, ramen, pizza or homemade croutons. It also works in place of part of the neutral oil in the aioli for a gentler result.

The buying logic is simple: pick whichever format suits how you already cook, and use it in this recipe.

A note on the recipe

Who thinks to tempura a radish? The idea sounds unlikely until you try it. Crispy battered bulbs with lacy, translucent leaves that turn out to be the best part of the whole plate. Deep frying is more of a special occasion activity than a weeknight move, but the next time you want to wow with something easy and fun, this is the one.

The aioli is a different matter entirely. It takes ten minutes, keeps in the fridge for at least a week, and once it's there you'll find uses for it constantly. We've been known to use it to upgrade frozen fries on a quiet night. No judgment.

Radish Tempura with Black Garlic Aioli
Serves 4

1 bunch small radishes with leaves

Aioli:
1 lg egg yolk, at room temperature
2-3 black garlic cloves, cut into pieces
2 tsp white wine vinegar
¼ tsp Dijon mustard
⅓ cup neutral oil (grapeseed or sunflower)
2 tbsp good olive oil
Salt and pepper to taste

Tempura batter:
¾ cup all purpose flour
3 tbsp cornstarch
¾ cup ice cold sparkling water

Garnish:
pinch Maldon salt and grated lime rind

1. Wash and dry the radishes thoroughly. Water is the enemy of batter adhesion and will cause spitting in the oil. Trim any damaged leaves. Pat everything completely dry and set aside.
   
   
2. Using a mini food processor or immersion blender in a vessel just wide enough to fit it, purée the egg yolk, black garlic, vinegar and Dijon to a smooth paste. Add the oils in a thin steady stream. Thin with a tbsp or so of cold water if desired. Season with salt and pepper.
   
   
3. Whisk together the flour and cornstarch, then add the sparkling water. You're looking for a batter about the consistency of heavy cream. You may need slightly more or less sparkling water. Mix at the last possible moment and keep cold until ready to fry.
   
   
4. Fill a wide heavy pot with a few inches of neutral oil and heat to 350°F. Working in batches, hold each radish by the leaf stem, dip through the batter, and lower carefully into the oil. Fry for 2-3 minutes, turning once, until the batter is pale golden and crisp. The leaves will go lacy and translucent. Don't crowd the pan or the temperature will drop. Drain on a wire rack.
   
   
5. Season with Maldon salt and grate fresh lime rind over top. Serve immediately with the black garlic aioli.