I bought this vegetarian meat substitute at a Japanese supermarket. One package (about 55,000 VND) is enough for 3 bowls.
Slice the tofu thinly and pan-fry until golden.

Marinate the vegetarian meat, fried tofu, and yuba:
Mix 1 tablespoon mushroom seasoning, 1 cube fermented tofu (chao) mashed with 1 tablespoon chao liquid, and finely chopped white part of leek. Add 1 tablespoon annatto oil and 1/2 teaspoon turmeric powder for color.

Slice half the carrot thinly.
Cut the remaining half (the thicker part) in half lengthwise, cut the loofah (or zucchini) into large chunks, and leave the onion whole.
I used reishi mushrooms, but after tasting, I think thinly sliced king oyster mushrooms absorb the flavors better and suit Mì Quảng more.

Add 3 cups water (about 700 ml) to the pot. Add the onion, loofah (or zucchini), carrot, and any leftover white leek. Season with 2 tablespoons mushroom seasoning and 1 teaspoon rock sugar. Bring to a boil, then lower the heat, cover, and simmer for about 20 minutes until the vegetables release their sweetness and the broth reduces by half.

Once done, remove all the vegetables and discard them. Add 1 tablespoon Hội An-style chili sauce to the broth.
How to make Hội An chili sauce:
https://cookpad.wasmer.app/vn/r/835688

To serve:
Place noodles and fresh herbs in a bowl. Arrange the simmered ingredients on top: mushrooms, vegetarian meat, fried tofu, yuba, and sliced carrot. You can add boiled eggs if you’re not following a strict vegetarian diet. Today I didn’t have banana blossom or baby mustard greens, so I just used what I had.

Ladle a small amount of broth over each bowl (about one ladle per bowl). Sprinkle with roasted peanuts (crushed or whole) and chopped green leek. Add more Hội An chili sauce if you like.

Serve with grilled rice paper, lime, and chili. Enjoy your vegetarian meal!