In a medium saucepan, bring the coconut milk and water to a boil. Stir in the rice and cover the pan. Reduce heat to a simmer and cook for 20 to 25 minutes, or until the rice has absorbed the liquid and is light and fluffy.
PREPARE THE CHICKEN CURRY:
In a large nonstick skillet, heat 2 tablespoons of the oil over medium-high heat. Once the oil is hot and shimmering, add the chicken and a sprinkle of salt and pepper, and spread the chicken into an even layer. Let cook for 2 to 3 minutes, then turn the chicken over and let the other side cook. Add 1 tablespoon of the ginger, 2 teaspoons of the garlic, curry powder, turmeric and cayenne. Stir and cook for a couple more minutes, until the chicken is cooked through. Transfer to a bowl, and cover with foil to keep warm. Wipe out the skillet with paper towels.
Add the remaining ½ tablespoon of oil to the skillet, and bring the skillet to medium-heat. Add the onion, jalapeno (if using) and zucchini. Sprinkle with salt, and cook until the onion and zucchini are softened- about 8 minutes. Stir in the remaining 1 tablespoon ginger and 1 teaspoon garlic. Pour in the tomatoes, and let it simmer for about 5 minutes (the tomato liquid should cook off a bit).
To serve, place a scoop of coconut rice in each serving bowl. Top with a portion of the zucchini/tomato mixture, chicken and a sprinkle of cilantro.