Dinner Tonight: Niku Udon Recipe

Name: Dinner Tonight: Niku Udon Recipe
Ingredients: For the Udon Broth:; 1 quart water, at room temperature; 1 large pieces of kombu, approximately 10 by 4-inches, or about 1/2 ounce total, rinsed; 1 1/2 cups packed katsuobushi (dried bonito flakes); 1/2 cup plus 2 tablespoons Japanese soy sauce; 1/2 cup mirin; For for the Niku Udon:; 8 ounces beef, very thinly sliced; 1/2 cup firm tofu, cut into 1/4-inch cubes; 2 scallions, ends trimmed, chopped into 1-inch pieces; 1 pound dried udon noodles; 1/2 cup watercress