Xiao didn't need to eat, he was a Yaskha, he felt neither hunger nor sleep. But that didn't allow him to not eat or not sleep. However, he did have one favorite food, and that was almond tofu. He couldn't explain why he liked it, but he said it "tasted like dreams."
One day, Xiao, while patrolling near the Wangshu Inn area, he had been attracted by the taste of tofu and almonds, sweet and warm, but he knew he couldn't get distracted that easily: on the other hand he was an adept, he had promised to protect Liyue, and that was what he would do until the end of his life
In the evening, while he was returning to the inn, he saw you, while Verr Goldet and Huai'an was congratulating you on the huge success of your almond tofu. They were helping you carry the plates and silverware away, to be washed and put away
You loved cooking. It was your passion since you were little, you started by burning pans and dirtying the kitchen, until you prepared a large amount of food and were evaluated for your skill. Xiao had stopped to observe for a few seconds, and your eyes had landed on him; so you had asked him if he wanted to try your almond tofu.
At first Xiao didn't say anything, he still had his spear in his hand, but then, for some reason, the scent of tofu reached his nose again. He wasn't hungry, he didn't care what you did, but for some reason he found himself accepting your proposal. He didn't show it openly, but when he tasted your dish, he was surprised that it was still good even though it had gotten cold. And somehow, you knew he liked it.
In the same casual way you had met, you continued to meet. You said you had become friends, he never commented on it, but when you called him to preview your dishes, he always came. And he had always tasted what you cooked, and although his compliments were not direct, you knew he liked what you cooked. You knew he liked them by the way he remained silent while tasting, the way he looked at the plate, then the way he looked at you.
"I don't know human tastes, but this might be liked" which was his way of saying that you had cooked something good
It was hard for Xiao to admit, partly because he wasn't used to spending much time with humans, partly because he had repressed his true nature for so long, but he loved the food you cooked. Even though his experience as a taster was limited to the very few things he had tasted in his entire life, what you cooked simply...warmed his cold hands. it warmed him inside.