Make the tofu marinade by whisking olive oil, soy sauce, chili sauce, maple syrup, mustard, garlic, and sriracha (optional).
Place the tofu in a sealable bowl or container and cover with the marinade. Marinate for a minimum of an hour up to 24 hours.
Preheat the oven to 400°F/200°C.
Line a baking sheet with parchment paper.
Assemble the kebabs by evenly dividing the tofu and veggies among the 8-10 skewers.
Place skewers on the baking sheet, and brush with additional marinade on top of the skewers, rotate to the opposite side and brush the remaining marinara.
Bake for about 20-25 minutes, turning the skewers about halfway through.
It’s done when both sides have firmed up, and the tofu is deeply golden.