Warm oil in a large skillet over medium heat. After 90 seconds when the oil is hot, add the tofu strips in a single layer. Cook for 3 minutes per side, turning carefully, until golden and crisp. Transfer the tofu to a plate and set aside, wiping down the pan to remove oil? and particles of tofu. *Alternatively you can air fry the tofu, or use pre-fried tofu cut into strips.
Bring a saucepan of water to a boil over high heat. When the water is boiling, add the green beans, remove from the heat and cover the pot.
In the same skillet you cooked the tofu in, warm oil over medium-high heat. After 90 seconds when the oil is hot, add the onion and green bell pepper and sauté for 4-5 minutes, stirring occasionally, until softened.
Finely mince the tender inner portion of the lemongrass stalks and add to the pan along with the garlic and curry powder.
Drain the green beans in a colander or wire mesh strainer.
After 3-4 minutes when the garlic is fragrant, add the green beans, the fried tofu strips, coconut sugar, water, and salt. Cook over medium heat for 4-5 minutes, stirring occasionally, until the green beans are tender and most of the liquid has reduced.
Transfer the lemongrass tofu to a serving dish with steamed rice on the side and garnish with sliced scallion, cilantro leaves, and bird’s eye chilies if desired. Serve warm.