Step 1

Preheat oven to 350°. Heat sugar, ½ cup vinegar, 2 Tbsp. soy sauce, and ⅓ cup water in a small saucepan over low, stirring to dissolve sugar. Add a quarter of mushrooms and half of ginger. Return to a simmer and cook 4 minutes. Let pickled mushrooms cool.

Step 2

Spread out cashews on one side of a baking sheet and coconut on the other. Toast, undisturbed, until most of coconut is golden brown, 5–7 minutes. Remove from oven; transfer coconut to a plate. Toss nuts; continue to toast until golden brown, about 5 minutes longer. Transfer to plate; let cool.

Step 3

Meanwhile, cook noodles according to package directions. Drain and rinse under cold running water. Set aside.

Step 4

Whisk kecap manis, 2 Tbsp. oil, remaining 2 Tbsp. vinegar, and remaining 4 Tbsp. soy sauce in a small bowl; set sauce aside.

Step 5

Heat 2 Tbsp. oil in a large pot. Cook remaining mushrooms, stirring occasionally, until browned, about 5 minutes. Transfer to a plate; wipe out pot. Heat 1 Tbsp. oil in pot; cook corn and beans, stirring occasionally, until tender, about 5 minutes. Transfer to plate. Reduce heat to medium; heat remaining 1 Tbsp. oil in pot. Cook shallots and remaining ginger, stirring, until softened, about 2 minutes. Return mushrooms, corn, and beans to pot and toss to combine, then toss in noodles. Add cashews, coconut, and reserved sauce and cook, tossing, until noodles are coated in sauce and warmed through, about 1 minute.

Step 6

Divide noodles among bowls and top with drained pickled mushrooms.