Esther's Japchae

Make the Dressing and Marinate the Beef:

1. In a bowl, whisk together all the dressing ingredients. Leave at room temperature while you prep everything else.
2. In a medium bowl, toss the beef with a few tablespoons of the dressing, just enough to coat. Leave at room temperature while you prep (or refrigerate overnight if prepping ahead).

Soak the Mushrooms:

1. In a small heatproof bowl, cover the mushrooms with 1 cup just-boiled water. Set a weight, like a small lid, on top to keep them submerged.
2. Let sit until softened, at least 20 minutes. Larger mushrooms can take 3 hours or more.
3. Drain and squeeze out the excess water. Trim and discard the stems, thinly slice the caps and set aside.

Cook the Vegetables Separately:

For the best texture, cut all the vegetables to the same size, a julienne about 2½ inches long. Use one large skillet for everything, adding just enough oil to lightly coat the pan before each batch, and mound each vegetable on a large platter as it finishes.

1. Onion: Heat 2 teaspoons vegetable oil over medium-high heat. Add the onion and a pinch of salt and cook, stirring often, until browned on the edges but still a little crunchy, 2 to 3 minutes.
2. Carrots: Add the carrots and a pinch of salt and cook until lightly charred but still crunchy in the center, about 3 minutes. Lower the heat if they start to scorch.
3. Bell peppers: Cook the green pepper with a pinch of salt until lightly charred but still crunchy, 2 to 3 minutes. Repeat with the red pepper.
4. Garlic and mushrooms: Lower the heat to medium. Add the garlic and cook no more than 30 seconds, then add the sliced mushrooms and a pinch of salt and cook until golden around the edges, 1 to 2 minutes.
5. Leave the platter at room temperature until you're ready to finish.

Cook the Beef:

1. In the same skillet, heat 1 teaspoon vegetable oil over medium-high heat.
2. Add the beef and its marinade and cook, stirring often, until cooked through, 3 to 4 minutes. It won't caramelize much because of the liquid. Add to the platter.

Blanch the Spinach:

1. Fill a bowl with ice water and bring a pot of salted water to a boil.
2. Add the spinach and cook for 1 minute. Lift it out with a spider or slotted spoon and plunge it into the ice water.
3. Once cold, squeeze the spinach dry with your hands, coarsely chop and add to the platter. Keep the pot of water boiling.

Cook the Noodles:

1. Stir the soy sauce and brown sugar into the boiling water. Add the noodles, using tongs to submerge them.
2. Cook according to the package directions, about 5 minutes, until translucent and soft.

Mix and Serve:

1. Drain the noodles in a colander (don't rinse), shake off the excess water and transfer right away to a large mixing bowl.
2. Add everything from the platter. While the noodles are still warm, pour in the remaining dressing and mix with your hands or tongs until everything is generously coated.
3. Taste and add more soy sauce or sesame oil if you like.
4. Transfer to a serving bowl, sprinkle with sesame seeds and let sit 10 to 15 minutes before serving so the flavors can meld.

Prep Ahead and Leftovers:

1. The day before, make the dressing and marinate the beef, refrigerating them separately. The mushrooms can also be soaked up to a day ahead.
2. Leftovers keep in an airtight container in the fridge for up to 3 days. The noodles firm up when chilled, so rewarm gently in a nonstick skillet.

Make it once for a potluck and it'll be on your table all season.