Aloo Gobi

2 tbsp canola oil
3 baking potatoes (1 ½ lbs) peeled and cut into 1″ pieces
1 small head of cauliflower (1lb) cut into 1″ florets
3 lg garlic cloves, minced
2 tsp finely grated peeled fresh ginger
½ tsp cumin seeds
½ tsp brown mustard seeds
½ tsp ground coriander
12 curry leaves (optional)
kosher salt and freshly ground pepper
1 lg tomato, chopped
1/3 cup frozen peas, thawed
1 tbsp unsalted butter
chopped cilantro, for garnish

In a large skillet, heat the oil. Add potatoes and cauliflower and cook over
moderate heat, stirring occasionally, until golden in spots, 7-8 minutes. Stir
in garlic, ginger, cumin seeds, mustard seeds, coriander, and curry leaves,
cook until fragrant, 1 minute. Season with salt 
and pepper and add 1 ½ cups of water. Cover and simmer over moderately
low heat, stirring occasionally, until the vegetables are tender, 15 to 20
minutes. Stir in the tomato, peas, and butter and cook for 2 minutes longer.
Transfer the aloo gobi to a platter, garnish with cilantro and serve