Hawaiian Dog

In a large skillet, cook 8 slices chopped bacon over medium until crispy, about 8 minutes; drain on paper towels. Thinly slice 1 red onion. In a small saucepan, simmer 1/2 cup distilled vinegar, 1/2 cup water, 2 tsp. sugar and 1 tsp. salt until sugar dissolves. In a small jar with tight-fitting lid, add onions and pour pickling liquid over. Cover and let sit at room temperature 1 hour, then refrigerate quick-pickled onions. Top dogs with diced pineapple, bacon, warm barbecue sauce, pickled red onion and pickled jalapeño slices.