Place tofu in a single layer on a paper towel-lined tray. Pat with extra paper towel to absorb excess moisture. Transfer to a large bowl. Mix spice blend, oil and garlic in a small bowl. Add half the spice mixture to tofu and toss to coat.
Place pumpkin, cauliflower, capsicum and onion on a large, shallow-sided baking tray. Drizzle over the remaining spice mixture and toss well to coat. Spread vegetables in an even layer. Bake in a preheated 220 °C oven (fan-forced) for 15 minutes.
Remove tray from oven. Drizzle honey over vegetables and turn to mix well. Scatter tofu over the top. Return tray to oven. Bake for a further 15 minutes or until vegetables are browned and tender.
Meanwhile, prepare couscous following packet directions.
Dollop yoghurt over tray bake. Sprinkle with mint. Serve with couscous and lemon wedges.