Kimchi is a traditional Korean fermented vegetable dish primarily made of napa cabbage. The key ingredients typically include:

• Napa cabbage (or Chinese cabbage)
• Korean radish (or daikon radish)
• Garlic
• Ginger
• Korean chili flakes (gochugaru) or fermented chili paste (gochujang)
• Salt (for brining/salting the vegetables)
• Fish sauce or salted shrimp paste (sometimes substituted with soy sauce, miso, or vegan alternatives)
• Spring onions or scallions
• Sometimes carrots and other vegetables are added

The cabbage and other vegetables are salted and brined to draw out moisture and preserve them. Then they are mixed with a spicy paste made of garlic, ginger, chili, fish sauce, and other seasoning ingredients before being packed tightly to ferment. The fermentation process develops kimchi's characteristic sour, spicy, savory, and umami flavors. In vegan versions, fish sauce or shrimp paste can be replaced by miso or soy sauce. Vegetables are sometimes pureed or pasted with added rice flour or sweet rice flour to aid the texture of the seasoning paste. So fundamentally, kimchi is made of salted and fermented napa cabbage (and radish) with a seasoning paste including garlic, ginger, chili powder or paste, and fish sauce or its alternatives.