3 ideas
Kimchi keeps changing as it ferments: fresh kimchi is crisp and bright, and it grows steadily more sour as lactic fermentation continues. Over-fermented, sour kimchi is not spoiled. It becomes the preferred ingredient for cooked dishes like kimchi stew and kimchi pancakes, where heat and fat balance the acidity.
A Korean home meal is rice and soup plus several small side dishes. The side dishes are made in batches ahead of time and kept in the refrigerator for days. Each weeknight meal is then assembled rather than cooked from scratch: only a soup or one main dish is made fresh, and variety comes from rotating the stored banchan.
A small set of fermented sauces does most of the seasoning in Korean cooking: soybean paste (doenjang), hot pepper paste (gochujang) and soy sauce (ganjang). Together with a basic stock such as anchovy and kelp, they supply the salt, savoriness and depth. Once a cook understands these few pantry ingredients, many recipes turn out to be variations on the same flavor base, not separate formulas to memorize.