Preheat the oven to 400°F (200°C).
Cut the drained and pressed extra firm tofu into ½ inch (slightly larger than 1cm) slices. In a bowl, mix lemongrass powder, fresh grated ginger, minced garlic, tamari, lime juice, white pepper, vegetarian oyster sauce, and sesame oil. Coat the tofu slices evenly with the marinade. Place on a parchment paper lined baking sheet and roast for 20-25 minutes or until golden brown.
While the tofu is roasting, prepare the spicy mayo by combining vegan mayonnaise, hoisin sauce, and sriracha in a bowl. Mix well using a small whisk or the tines of a fork and set aside.
For the Quick Pickled Veggies, place the salt and sugar in rice vinegar and water into a saucepan and bring it to a boil.
Pour the hot brine into a bowl over the shredded carrot, thinly sliced Persian cucumbers, and julienne-cut or shredded daikon. Let them marinate and cool for at least 15 minutes.
To assemble the Vegan Bánh Mì, slice an 18-inch baguette horizontally. Optionally, you can toast the baguette’s cut side for a few minutes over medium heat in a skillet or griddle pan.
Spread a generous amount of Spicy Bánh Mì Mayo on both halves of baguette. Place the roasted tofu on top, followed by the quick-pickled veggies. Garnish with fresh cilantro sprigs and thin rings of jalapeño.
Close the sandwich with the top half of the baguette. Slice into individual portions and get ready to smash this delicious Vegan Bánh Mì!