1.Drain tofu; pat dry. Cut each block of tofu lengthways into four thick slices. Combine rind, juice, garlic and pepper in a shallow glass or ceramic dish. Add tofu; turn to coat. Cover; refrigerate for 3 hours, turning occasionally.
2.Meanwhile, combine flours, polenta, baking powder, salt, garlic and onion powders in a medium bowl. Gradually whisk in beer until the consistency of pancake batter. Cover; refrigerate for 1 hour.
3.In the last hour of refrigeration time, preheat oven to 220°C/425°F. Line an oven tray with baking paper.
4.Place sweet potato on tray, drizzle with oil and season. Toss to coat. Roast for 45 minutes or until tender.
5.Make spice mix.
6.Heat the extra oil in a large saucepan over medium-high heat. Dust tofu in extra cornflour; shake away excess. Dip tofu in batter; drain away excess. Shallow-fry tofu, in batches, for 1 minute each side or until golden on both sides and heated through. Drain on paper towel.
7.Sprinkle tofu and sweet potato wedges with spice mix; serve with lemon wedges. Season to taste.
8.Combine ingredients in a small bowl.
You can use soda water instead of beer, if you like. Leave the skin on the sweet potatoes for extra flavour and nutrients; wash and dry them first before cutting into wedges.
Serve with a vegan tartare sauce.Note