Mixed Vegetables, Bacon and Cheese Rolls

Overview

This is my first time trying to make meaty bread.

Put the other ingredients except butter together, knead until the surface of the dough is smooth, add softened butter and knead until the expansion stage, put it in a basin, cover with plastic wrap and let it ferment in a warm place.
Make the filling: Cut the bacon into fingernail-sized pieces, put them in a pan and stir-fry them to dry them out.
Add mixed vegetables and pepper and mix well.
After the dough has fermented, take out the dough to deflate, roll it into a ball and let it rest for 15 minutes.
Slowly roll the relaxed dough into a rectangular shape, thinning one side.
Spread the filling evenly on the dough and press it down with a spoon.
Sprinkle with mozzarella cheese.
Roll up and divide into 8 equal portions.
Arrange into baking pan. (If it is a non-stick baking pan, remember to brush it with oil)
Place it in a warm place for final fermentation. After the fermentation is completed, brush the surface of the dough with egg wash, and then squeeze an appropriate amount of salad dressing in a "Z" shape.
Put it in the oven at 180 degrees, upper and lower heat, middle and lower layers, and bake for about 25 minutes.