Peel the onions and apples, cut into large pieces, then place them in a saucepan with 50 ml water. Cover and cook over low heat until very soft and the water has evaporated, about 8–10 minutes.
Add the green curry paste, fish sauce, chopped lemongrass, soy sauce, brown sugar, and coconut milk to the softened onion-apple mixture. Blend with an immersion blender or in a countertop blender until smooth and creamy.
Cut the chicken into thin strips. Slice the zucchini, red pepper, and mushrooms. Prepare the bamboo shoots, baby corn, and hot pepper.
Return the blended sauce to the pot and bring to a gentle boil. Add the chicken strips, zucchini, red pepper, mushrooms, bamboo shoots, baby corn, and hot pepper. Cook uncovered for 3–4 minutes after it starts boiling, until the chicken is cooked through and vegetables are tender-crisp.
Stir in the fresh basil leaves just before removing the curry from heat.
Meanwhile, bring 600 ml salted water to a boil in a separate pot, add the rinsed rice, then reduce to low heat and cook until the water is absorbed and the rice is tender.
Serve the curry over the cooked rice.