Heat oven to 425°F. On rimmed baking sheet, toss tofu with 1 tablespoon oil, then gochugaru and ½ teaspoon salt and roast 15 minutes. Flip and roast until golden brown, 8 to 10 minutes more.
Meanwhile, heat 1 tablespoon oil in Dutch oven on medium. Add chopped scallions, ginger, and jalapeño and cook, stirring occasionally, 2 minutes. Add broccoli stems and cook, stirring occasionally, 5 minutes. Add garlic and cook, stirring often, 1 minute.
Add coconut milk, bouillon base, and 2 cups water and cook, stirring, until bouillon base dissolves, about 30 seconds. Add broccoli florets and ½ teaspoon salt and bring to boil. Reduce heat to simmer, cover, and cook until broccoli is tender, 8 to 10 minutes.
Remove from heat, add spinach and cilantro and using immersion blender, blend until smooth. Serve soup topped with tofu, scallion greens, and additional gochugaru, if desired.
