Heat a wok over medium-high heat. Add the rice and dry fry while stirring until golden brown. Remove, cool, and grind.
Add to the wok the chicken, fish sauce, lemongrass, and water. Cook while stirring to make sure the chicken breaks up and becomes crumbly. Remove as soon as cooked through but still moist, about 5 minutes.
Stir the lemon juice, onions, scallions, cilantro, mint, peanuts, chili flakes, and ground rice through the chicken. Toss well to combine; the residual heat will make the added ingredients fragrant without cooking them.
Lay out the endive leaves, then divide the chicken salad amongst them. Arrange on a plate ready to serve; eat while still warm.