For the sauce: Combine the sugar, tamari, rice wine vinegar, sesame oil and ginger in a small bowl. Whisk until the sugar is dissolved. Set aside.
For the noodles: Bring a large pot of salted water to a boil. Add the noodles and stir to help submerge them. Cook until the noodles are just barely cooked, 6 to 8 minutes. Drain and rinse with cold water. Using kitchen shears or a clean pair of scissors, cut the noodles into approximately 8-inch lengths. Set aside.
Heat the grapeseed oil in a large skillet over high heat. Add the oyster and shiitake mushrooms and cook, stirring often with a wooden spoon, for about 5 minutes, or until the mushrooms are beginning to brown. Add the shallots and 1/4 teaspoon salt and cook until fragrant, another 2 minutes. Add the red pepper, garlic and scallions to the pan, reduce the heat to medium-high and cook for an additional 3 minutes, or until the peppers are beginning to soften. Add the kale and the cooked noodles and saute another 3 minutes, stirring often to coat the noodles in the oil and to wilt the kale. Add the sauce and toss to coat. Top with sesame seeds if desired.
Recipe courtesy of Giada De Laurentiis