Fry the meat with the garlic until the meat is cooked through and lightly browned. Add the mushrooms, onions, carrots, turnip and cabbage and sauté for about 5 minutes over medium heat. Then season with the soy sauce, the salt, a little pepper, the oyster sauce and the sherry and continue to fry briefly.
For the homemade spring roll leaves, mix the flour, salt and water. Spread a good tablespoon of dough thinly in a lightly oiled pan over low heat and remove it immediately as soon as the dough is no longer moist (see video). This approach results in between 26 and 28 small spring roll leaves.
Divide the filling between the spring roll leaves, coat each edge with flour glue, roll up (see video) and deep-fry until golden brown.
For the sauce, cook the vinegar together with the sugar to a syrup over medium heat, allow to cool a little and mix in the remaining ingredients.