To make mash: Preheat the oven to 390°F Prick each sweet potato with a fork several times and wrap in foil. Bake in the hot oven for 30-45 minutes until soft. Remove the foil and add to a large bowl. Add yogurt or cream, maple syrup, and salt to taste. Mash and stir until well combined. Serve warm.
Combine cornstarch, powdered stock, paprika, cayenne, and a little salt and pepper to taste in a shallow bowl. Toss the cubed tofu in this mixture until well coated on all sides.
Heat 1 tsp of vegetable oil in a large fry pan. Add the cubed tofu and a good sweet of lemon juice. Toss over medium heat for 2-3 minutes, browning pieces on all sides.
Add cherry tomatoes, raisins, and remaining juice from one lemon. Continue to cook over medium heat, adding 1-2 tbsp of stock at a time, allowing the stock to reduce before adding more. The cornstarch will begin to create a thick gravy-like sauce as you add stock. Continue to cook until all the stock is added, the tofu is nicely browned, and the cherry tomatoes are soft and wilted.
Just before serving, toss the baby spinach with the tofu mixture and combine well. Serve the braised tofu on top of the kumara mash and accompanied with brown rice, if desired.