I love Berliner Supermarkt. It's a genuine Turkish bakkal - it's like a German Spati meets a mini…read moresupermarket, minus the booze. What this means: you can go in there for some of the best produce in Tegel, far better than at Rewe delivery or the sad salads at Edeka. Their meat counter is also amazing, and they also have fine Turkish meze appetizers. Spices and nuts are cheap and plentiful; olives are the real deal, same brands as you'd find in Istanbul. What you will not find is things like milk, western coffee, cereal, etc. - for that, you'd have to go to the Edeka to supplement. But this place is a gem and should form the basis of your shopping. The only thing I'd really avoid here are cashews (which are really hit or miss). The owners here are super-friendly, but the main guy is really shy, barely looking you in the eye and speaking softly, with an arabesque melancholy in his voice; his humility and awkwardness make him look sad or brusque, but he's actually super-friendly. (The first time I was there, I thought he was like the Grim Reaper, and I called getting produce there "reaping.") The other workers are super helpful, either recommending the best brands of tahini or sucuk, or helping you find the dried mint. Really: go.