Corn, Mushroom and Green Pepper Subji

1 cup of frozen corn kernels (if you use fresh, cook them at the same time as the mushrooms)
1 large green pepper (Cut the pepper into half, and then into 1/2-inch strips.)
2 cups of mushrooms quartered
1 large onion, finely minced

1 tbsp grated ginger

1 tbsp minced garlic

1 tbsp coriander powder

1 tsp cumin powder
1 tsp red chili powder
1/2 tsp turmeric
1 tsp garam masala (I grind cinnamon sticks, cloves, cardamom, and peppercorn but you can buy at the Indian grocery store)
1 tsp olive oil

1 cup diced tomatoes

1 tbsp tomato paste

2 tbsp salted butter
Salt to taste

Heat the oil and saute the onions until they start to turn golden-brown. Add the ginger and garlic and saute another minute over medium heat. Add the tomatoes and tomato paste. Saute over high heat for about 2 minutes or until the oil begins to express. Lower the heat to medium. Add the coriander, cumin, turmeric and chilli powders and stir. Add the mushrooms and stir well. Add salt to taste. Cook for about five minutes until the mushrooms are cooked. Now add the green peppers and frozen corn. Cook another five minutes. Add the garam masala. Add butter.
Garnish with coriander and serve hot with Indian bread and fresh plain yogurt.