Preheat oven to 350 F /175 C.
To prepare the skewers, thread a piece of pastrami onto the skewer first, and then a tender, starting at one end of the chicken and weaving the pointy tip of the skewer in and out about three times, until the chicken is in an "S" shape. Push it down to compress it into the centre of the stick. Use 2-3 tenders for the middle of each skewer, and finish with another piece of pastrami. Lay the skewers on a baking sheet, making sure they don't touch so they can crisp up nicely.
Add olive oil to a small shallow bowl and brush over the skewers, coating the chicken and pastrami on one side ONLY. No need for extra work. Alternatively, you could spray with baking spray, but, personally, I like the taste of the olive oil.
Add the brown sugar to a pinch bowl and sprinkle a little over the pastrami, to help it crisp and caramelise a bit.