I've been making normal kimchi (with Chinese cabbage) in a big way for years now, but that's the only kind I've made. In December 2006, after making my last batch of kimchi, I had a giant radish (Radi or daikon) left over. I have a cook book by Copeland Marks called “The Korean Kitchen” with a recipe for kaktugi kimchi, basically made only from Radi. Some of the details seemed unlikely, so went out Googling for other recipes. I found the same one multiple times (easily identified by the requirement for a “head of garlic”), and no other. Partially this would be explained by the transliteration; I've also seen the spellings kkakdugi and kakdugi, but no useful recipes to go with them. So decided to do my own; this is the result.

Giant radishes are white and carrot-shaped, about 25 cm long and 8 cm across at the top. The are often sold under the name Daikon or Chinese radish. They're well-known in Europe as well. In Germany, they're called Radi.

The chili flakes are the same as used for cabbage kimchi. I'm not sure how important the choice is. I use coarse chili flakes from a Korean grocer. You can probably use fine chili powder as well, but it's difficult to guess how strong it will be in comparison.

The original recipe specifies dried prawns rather than fish sauce; elsewhere I find the statement that this makes it darker. I don't have dried prawns, and I'm not very fond of them, so I used Korean fish sauce this time. This isn't the same as Vietnamese fish sauce.

The original recipe includes no liquid whatsoever. Given that the chili flakes are dry, I'd guess that this is an error in the recipe. I've found empirically that the 35 ml total liquid give a very dry mixture.

The quantities match the size of the Radi I had left over. The original recipe “makes a quart” and uses 1 lb (450 g) of Radi.

Preparation

Cut the radish into cubes. The original recipe specifies 1 inch (2.5 cm), which I find far too large. I chose 1.5 cm for this time. Finely chop garlic and ginger. Mix all together and leave at room temperature for a day, then refrigerate. To quote the multiply replicated recipe on the web,

It is ready to eat immediately but it may be stored in the refrigerator for several months. Serve with any kind of Korean food as a side dish.