Get the oven and pot ready: Heat the oven to 400°F with a rack in the middle. Set a 3- to 4-quart Dutch oven or another oven-safe pot with a lid on the stove.

Put the basmati rice in a fine-mesh strainer. Rinse it under cold water until the water looks much less cloudy, then let the rice drain well.

Stir together the yogurt: In a small bowl, stir together the yogurt, 1/4 teaspoon of the cumin, 2 tablespoons water, a small pinch of the salt, and half of the chopped cilantro. Set the bowl in the refrigerator while you make the casserole.

Place the Dutch oven over medium heat. Add the oil and let it warm for about 30 seconds.

Add the chopped onion to the pot with 1/2 teaspoon of the salt. Cook for 6 to 8 minutes, stirring often, until the onion is soft and lightly golden at the edges.

Start the casserole: Add the garlic, ginger, the remaining 3/4 teaspoon cumin, and the garam masala to the pot. Stir for about 30 seconds, just until the mixture smells fragrant.

Add the drained rice to the pot. Stir for 1 minute so the grains are coated with the oil and spices.

Pour the tomato sauce into the pot. Stir well and scrape the bottom of the pot so nothing is sticking.

Pour the vegetable broth into the pot. Stir again until the tomato sauce loosens into the broth.

Add the kidney beans, frozen peas, the remaining 1 teaspoon salt, and the black pepper to the pot. Stir until everything is evenly combined.

Raise the heat to medium-high and bring the mixture to a strong simmer. You should see steady bubbles across the surface.

Bake the casserole: Put the lid on the pot. Transfer the covered pot to the oven and bake for 25 minutes.