2 tablespoons vegetable oil
2 garlic cloves, minced
2 teaspoons grated ginger
1 onion, thinly sliced
1 teaspoon ground cumin
1 teaspoon mustard seeds
1 teaspoon chili powder
1/2 teaspoon turmeric
1 1/2 teaspoons garam masala
1 head cabbage, cored and chopped
2 russet potatoes, peeled and chopped
2 plum tomatoes, chopped
1 cup tomato sauce
2 teaspoons salt
1 cup frozen peas
Heat the oil in a large skillet over medium-high heat.
Add the garlic, and cook for about 1 minute.
Add the onion and ginger, and cook, stirring, until softened, about 5 minutes.
Add the cumin, mustard seeds, chili powder, turmeric and garam masala, and cook, stirring, for 30 seconds.
Transfer the mixture to the slow cooker, using a rubber spatula to scrape out the ingredients to make sure you get all the spices.
Add the cabbage, potatoes, tomato sauce and salt to the slow cooker. Stir to mix well.
Add the chopped tomatoes and stir to combine.
Cover and cook on low for 4 hours.
Stir in the peas, cover again, and cook for 30 minutes more.
Serve hot.