Cover and cook rice in boiling salted water over low heat, pour into a sieve, rinse off ice cold, drain very well and allow to cool.
Peel the onion and garlic and dice very finely. Heat 1 tablespoon of oil in a pan and briefly fry the minced meat. Add onion and garlic and stir-fry the meat until crumbly. Season with salt and pepper, remove from heat and allow to cool.
Beat the apple cider vinegar, oil and mustard in a bowl with a whisk. Season to taste with salt and pepper. Add the minced meat and rice, mix well and let the salad steep for a moment.
In the meantime, wash and core the tomato (you can also use red pepper, by the way) and dice it very small. Wash 1 bunch of chives, cut into small rolls and mix with the lettuce with the diced tomatoes. Season again and season if necessary, the rice absorbs a lot of seasoning.