Add the potatoes to a large pot of salted water. Bring water to a boil over high heat, then reduce heat to cook at rapid simmer until potatoes are easily pierced with a knife, about 15 minutes depending on size.
Meanwhile, heat the oil in a large, deep non-stick skillet or wok over a medium heat, and fry the mustard seeds until they crackle and pop.
Half or quarter the cooked potatoes (depending on size) and add them to skillet with then cabbage. Stir well to incorporate. Then add the mustard, water, sugar, salt, salt, and lemon juice and stir until well combined.
Serve and enjoy!
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