Rinse jasmine rice under cold water until water runs clear, then soak for 30 minutes. Drain and add to a medium saucepan with water, salt, and coconut oil. Bring to a boil, then reduce heat to low, cover, and simmer for 18 minutes. Remove from heat and let stand 10 minutes before fluffing with a fork.

Season fish chunks with salt, pepper, and half the lime juice. Set aside to marinate while preparing other ingredients.

Heat coconut oil in a large, deep skillet or wok over medium heat. Add diced onion and cook until softened and translucent, about 5 minutes.

Add minced garlic and grated ginger to the pan, stirring constantly for 1 minute until fragrant.

Stir in red curry paste and cook for 2 minutes, allowing it to bloom and become fragrant.

Pour in coconut milk, fish sauce, and brown sugar. Bring to a gentle simmer, stirring to combine all ingredients smoothly.

Add bell pepper and cherry tomatoes to the curry. Simmer for 5 minutes until vegetables begin to soften.

Gently add the marinated fish chunks to the curry, being careful not to break them apart. Simmer for 8-10 minutes until fish is cooked through and flakes easily.

Remove from heat and stir in remaining lime juice, lime zest, minced Thai chilies (if using), and half the cilantro.

Taste and adjust seasoning with additional fish sauce, lime juice, or brown sugar as needed.

Serve immediately over fluffy jasmine rice, garnished with remaining cilantro and fresh Thai basil leaves.