Boil corn in a microwave oven. Chop onion and garlic. Heat 1 tbsp olive oil in a non-stick pan, add onion and garlic and sauté. Chop the blanched spinach leaves and add. Chop green chilli, add and mix. Remove corn from microwave oven, drain and add along with salt, pepper powder and mix well. Transfer the mixture into a bowl, add cheese and mix. Spread the mixture evenly on 4 bread slices, cover with remaining slices. Drizzle some olive oil over each sandwich. Heat a sandwich griller, drizzle some olive oil over it and grill the sandwiches till both sides are evenly golden. Cut each sandwich into 3 strips and serve hot.