In a medium Dutch oven, heat the canola oil and butter over medium-high heat. Add the onion and cook, stirring occasionally, until lightly browned, about 10 minutes. Add the cabbage, sugar, mar- joram, and 1½ tsp salt and stir to combine. Turn the heat to low and cook until the cabbage is soft, about 20 minutes.
Meanwhile, fill a large pot three-fourths full with water, season the water with enough salt to make it almost as salty as seawater, and bring to a boil over high heat. Drop in the noodles, stir to prevent them from sticking together, and cook until almost tender, 3 to 4 minutes. (They will cook more with the cabbage mixture.)
Drain the noodles, add them to the cabbage mixture, and continue to cook, stirring occasionally, until heated through and the noodles have absorbed some flavor from the cabbage mixture, about 6 minutes. Season with salt and pepper and serve immediately.