7/8 cup dry red split lentils
1 teaspoon ground turmeric
2 cups vegetable stock or water
1 tablespoon vegetable oil
1/2 stick unsalted butter
1 teaspoon black mustard seeds
2 teaspoons cumin seeds
1 bay leaf
10 curry leaves (fresh are best, but dried will do)
1 Serrano chile, finely chopped
1 small onion, finely chopped
4 cloves garlic, finely chopped
One 2-inch piece fresh ginger, peeled and finely grated
1 large plum tomato, roughly chopped
Fine sea salt
1 tablespoon freshly chopped cilantro, to garnish
Roti bread, to serve