Udon Noodle Soup

Yes, make the broth up to 3 days ahead and refrigerate in an airtight container. Reheat gently over medium heat until steaming before cooking the noodles and toppings; the flavors will actually improve slightly.

Simmer 2 pieces kombu (about 3 inches each) in the stock for 5 minutes, remove them, then add 1 oz bonito flakes, steep for 3 minutes, and strain through cheesecloth or a fine-mesh strainer. This takes 10 minutes but tastes noticeably better than powder.

Overcooking is the most common mistake. Fresh udon noodles cook very quickly (3–4 minutes); do not let them sit in water before cooking, and drain and serve them immediately after cooking. Set a timer and check at the minimum time.

Absolutely—eggs are traditional but optional. Simply omit them and add more fish cake, a slice of tofu, a handful of spinach, or mushrooms instead.

Beyond the classic egg, chicken, and green onions, try sliced mushrooms (sautéed first), blanched spinach, tempura, thin slices of beef, fish cake, or nori (seaweed) strips. Add toppings that are either cooked or don't need cooking.

Store broth and noodles separately in the refrigerator for up to 3 days. To reheat, warm the broth alone over medium heat, then add fresh noodles and cook as directed, or briefly warm leftover noodles in the reheated broth. Cooked noodles stored in broth will soften; plan to cook fresh noodles if the soup will sit more than a few hours.