Prepare a large sized pan on medium heat with oil until hot. Start cooking the rice while the pan is heating. Pour the coconut milk into a medium saucepan. Then, stir in the brown sugar, jasmine rice, olive oil, and season with salt. Bring to bowl and stir.
Cut chicken into cubes and marinate with salt, pepper, and ground annatto. Place the chicken into the large frying pan when the onion, peppers, and garlic is done sautéing.
While chicken is cooking, remove rice saucepan from heat and set aside, leave still covered. When chicken breast cubes are cooked, add diced mango, mango nectar, chicken broth, butter, and juice from half a lime.
Stir and boil on medium/high heat. Reduce heat while sauce thickens to desired consistency. Serve over coconut rice and garnish with cilantro.