Genli is just trying to provide food for Rito Village in The Legend of Zelda: Tears of the Kingdom. As the blizzard continues to rage on, she wants to help keep everyone full and healthy.
Her quest, Genli’s Home Cooking, sees you helping her get ahold of a specific fish that she needs for a recipe. Fortunately, this fish is really close and won't take you long to find at all once you know where to look.
Start Genli’s Home Cooking
After arriving at Rito Village and speaking with the three kids about their song, they will all go do their own thing. You can find Genli up a little way on the stairs, standing in front of a pot, apparently in distress. If you speak with her, she will tell you that she wants to make a specific recipe but is missing the last ingredient: Staminoka Bass.
She will ask you to find it for her, since she can't go out on her own as a child to look for it. Accept her request and get ready for a really short walk.
Complete Genli’s Home Cooking
The truth is that Genli could have easily gotten the fish herself without barely leaving the village. On the series of islands that lead up to the village - all connected by bridges - the Staminoka Bass is on the one closest to the village.
Head to the first floor, and walk over to the island, and look to your left. Here is a very small pond with a couple of fish swimming around in it. It's shallow, so you can just jump in and grab one or both of the fish. The pond is small enough that even with the fish trying to swim away, they won't have anywhere to go, and you can just get them immediately.
With the Staminoka Bass in-hand, head back up to Genli and hand it over to her. She will thank you for your help and give you a reward in the form of a delicious meal: Biting Simmered Meat. And now, the quest has come to an end.