Lightly spray a baking sheet or pan with oil. Place the slices of tofu one beside the other, not touching, on the sheet and spray the tops with the oil spray.
Bake the tofu in a preheated, 350-degree oven for 30-45 minutes or until the tofu is lightly golden-brown. When cool enough to handle, cut the tofu into a dice. Set aside.
Heat the oil in a large saucepan. Add the diced onions and a pinch of salt.
Saute the onions for five minutes or until they start to get brown spots.
Add the ginger and turmeric, stir to mix, and add the squash and green bell peppers.
Saute, stirring frequently, for five minutes or until the vegetables start to get tender. Add the sambar powder or curry powder, stir well, then add the vegetable stock or water and bring to a boil.
Cover the saucepan and let the curry simmer for 2-3 minutes. Add the tofu and chickpeas and mix well. When the mixture begins to boil, lower the heat to a simmer and add the coconut milk.
Let the curry warm through without coming to a boil. Turn off the heat, add salt to taste, spring onions, cherry tomatoes and lime juice. Stir.
Garnish with coriander leaves and serve hot.