Cooking Steps

• Bring a large pot of salted water to a boil. Add 8 ounces dried noodles and cook for 1 minute less than the package instructions. Meanwhile, whisk ¼ cup soy sauce, 2 tablespoons rice vinegar, 1 tablespoon of the toasted sesame oil, 1 tablespoon honey, 2 teaspoons cornstarch, 1 teaspoon Asian chili-garlic sauce if using, and 2 minced garlic cloves together in a liquid measuring cup or small bowl.
• Drain the noodles and rinse well under cool water.
• Heat the remaining 1 tablespoon toasted sesame oil in a large high-sided skillet over medium-high heat until shimmering. Add 1 pound lean ground beef and season with ½ teaspoon kosher salt and ¼ teaspoon black pepper. Cook, breaking up the meat into medium pieces, until browned and cooked through, 5 to 7 minutes. In the last minute of cooking, stir in 1 tablespoon sesame seeds.
• Reduce the heat to medium. Stir in 8 ounces baby spinach a few handfuls at a time. Whisk the sauce again, then add the sauce and noodles to the skillet. Cook, tossing regularly, until the spinach is just wilted and combined well with the beef and noodles, about 1 minute. Garnish with more sesame seeds and thinly sliced scallions if desired.