Yam Soup Chinese – A Cozy Autumn Bowl

Name: Yam Soup Chinese – A Cozy Autumn Bowl
Ingredients: 1 Chinese yam (about 200 g); 80 g all-purpose flour; 2 medium tomatoes (about 250 g); 2 eggs; 10 g dried wood ear mushrooms (soaked in water, shredded; about 80 g after soaking; optional); 100 g leafy greens (spinach, bok choy, or similar; use tender leaves); 2 scallions (1 for stir-frying, 1 for garnish); 3 g salt (use in two steps: 1 g for tomatoes, 2 g for soup; adjust to taste); 15 ml light soy sauce; 3 g chicken bouillon powder (or a drizzle of sesame oil instead); A few drops sesame oil (optional, for finishing); 1 tbsp cooking oil (for stir-frying); 800 ml water (or stock for richer flavor)