We visited Shuanglian Market on a Saturday, from about 10:30am to about 12:00pm and found the atmosphere still alive with locals shopping for groceries and cooked food. As we had no means to cook or heat food in our hotel room, we decided to purchase only that which we could consume without cooking or heating.
The market had an amazing variety of fruit and vegetables. We purchased freshly squeezed carrot juice for NT$80.00 for one litre. There were many other vendors selling deferent types of freshly squeezed juices for about the same price.
You could purchase freshly cooked meats, chopped into edible pieces and boxed for very reasonable prices. The market sold cooked meats, and fresh meat, fish, seafood etc. There was a vendor selling sushi pre-boxed or unboxed so that you can choose your own mix. There were vendors selling pre-packaged fresh soup mixes; and vendors selling soup to eat at the market. We saw many locals purchasing their lunches for the day from this market. One of the most popular stalls was the freshly made, unfried, large spring rolls.
The most important aspect of this market was its vendors and the people shopping there. We found the locals to be very approachable, friendly and helpful. It is easy to get to, and well worth a visit if visiting Taipei.