simmer, cook over slow fire
燜 centers on gentle, enclosed cooking: simmering or stewing over a slow, low fire, often with a lid or covered pot.
燜 combines 火 (fire) with 悶, which likely contributes the sound モン and the idea of something enclosed or suppressed, fitting the slow, covered cooking method.
Fire 火 on the left, and 悶 (agony, worry) on the right. Picture a cook agonizing over a covered pot, simmering the food slowly so it doesn't burn—the fire is low and controlled.
For モン, imagine a monk (モン) patiently simmering a stew over a slow fire, meditating while the pot gently bubbles.
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