Preheat oven to 375 degrees. Line a baking sheet with aluminum foil and top with a baking/cooling rack. Lightly spray the rack with non-stick spray.
Cut kielbasa down the middle, lengthwise. Slice each half into 1-inch pieces (you should have about 30 pieces total). Cut each piece of bacon into thirds. Wrap one bacon strip around each piece of kielbasa and secure with a toothpick. Set aside.
In a small saucepan, combine brown sugar, vinegar, mustard and pepper. Heat over medium heat, stirring occasionally, until the sugar is dissolved. Keep warm on low.
Brush the kielbasa with glaze and place on the baking sheet/rack. Bake for 40 minutes and baste every 15 minutes. Serve immediately.
