Cut tofu, zucchini, onion, mushrooms, and green onion into bite-sized pieces.
Make broth by boiling 300ml of water with anchovies and kelp in a pot.
Remove the anchovies and kelp, then add onion, zucchini, and mushrooms, and continue boiling.
Season with red pepper powder and minced garlic.
Add soft tofu and simmer on low heat for 3 minutes.
Adjust the seasoning with salt or soy sauce, then top with green onions.