According to pretzel bread recipe, raw dough buns must be dipped for 30 seconds into a water with baking soda before going into the over in order for them to develop that pretzel brown crust, but it also seems to make the crust quite hard. Is there anything I should add or do to make the pretzel bun's crust soft like this:
All the recipes I tried to follow on the internet came out with a very hard pretzel crust.
Since what you're making is a pretzel that you want to act like a soft loaf, I would try treating it like a bread.
To keep the crust on homemade bread soft, people brush the top with a fat of some kind (usually butter). So you could try liberally brushing the tops of your buns with butter when they're fresh from the oven and still hot. That should keep the "crust" of your mini-loaf nice and soft.
Dipping pretzels in an alkaline solution is what makes the outside brown and hard. If you want them to be less brown and hard, just dip them for a shorter period of time - they would be soft and white if you didn't dip them (or if you dipped them in plain water).
