Heat the oven to 400°F with a rack in the middle.

Rinse the basmati rice in a fine-mesh strainer under cold water until the water runs mostly clear. Let the rice drain well.

Set a 4- to 5-quart Dutch oven or other oven-safe pot with a lid on the stove over medium heat. Add the olive oil.

Add the chopped onion to the pot with 1/2 teaspoon of the salt. Cook for 5 to 6 minutes, stirring often, until the onion is soft and lightly golden at the edges.

Add the grated ginger and chopped garlic to the pot. Cook for 1 minute, stirring, until fragrant.

Add the curry powder and black pepper to the pot. Stir for about 30 seconds so the spices bloom in the oil and smell toasty.

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

Add the drained chickpeas to the pot. Stir once to mix them through the rice and onion mixture.

Pour the coconut milk and water into the pot.

Add the frozen spinach and the remaining 1 teaspoon salt to the pot. Stir and break up any large frozen clumps so the spinach starts to spread through the liquid.

Raise the heat to medium-high and bring the mixture to a gentle simmer. Once you see small bubbles around the edges, stir once and turn off the heat.

Cover the pot with its lid and transfer it to the oven.