Bow Dip burger from Bun and Sum

I have always wanted to try this burger place because of the bow dip burger which comes with a pot of beef juice for dipping.
Buns & Some is a delivery kitchen that turned popular hence people are coming here for takeaways.
Located underneath railway arches, there is no where to sit unless it is a media visit with the usual arrangements.
Overall, the burger was soft and reminded me of shake shack with extra brisket slices.
The beef juice which I was looking forward to was a bit salty so couldn't finish it.
Overall I was glad I tried, it is interesting how East London is changing as well as rail arches with more kitchens moving in amongst those car garage places.