In a large bowl, put the dough ingredients and stir using a strong spoon until smooth for about 6 - 7 minutes. We can use a mixer for about 4 - 5 minutes.
Cover the dough in the same bowl you're using, for 1-2 hours at a warm place. A colder place will take longer.

Meanwhile, cook the filling. Brown the onions until softened and add carrot & green onion, stir briefly, and add the chicken. Stir well.
Add the flour and stir evenly. Pour the milk, stir and cook over medium until the milk dry, cool down.
Take the dough out from the bowl onto a floured counter and shape into a ball.
Divide the dough into 10 pieces, shape into balls.

Flatten the small dough into an rectangular or oval and thin using a rolling pin. Add 1-2 tblsp of the filling at the edge. Add some grated cheese on top.
Wrap it up, the same way when you make egg rolls or spring rolls.
Put in a baking pan or just simply arrange on a baking sheet/tray. Cover for 1 hour at a warm place.

10 - 15 minutes before baking time preheat the oven at 180°C
Egg wash using 1 tblsp egg from the dough. Sprinkle with sesame seeds and parsley if you like, but it adds the flavor.
Bake for 20 - 25 minutes at 180°C top-bottom heat OR 20 minutes at 160°C fan mode. An oven may vary.
For the stretchy cheesy moment, please serve while still warm-hot.

#Tips:

Considering the fillings I suggest consuming it on the same baking day.

To freeze after baked, after cool, put in a freezer plastic bag/container up to a month.

Defrost at room temperature until soft again before reheating.

You can use a leftover chicken as well in this recipe.

You can used your favorite vegetables in this recipe.

You adjust the seasoning according to your preferences.