Place Brussel sprouts in boiling water for appx. 6 minutes. (For frozen, prepare according to instructions), drain. Fry bacon until crispy and set aside. Leave the hot bacon grease in skillet. Cut ends off the Brussel sprouts and cut in half. Place flat-side down in bacon grease. Fry over medium heat until edges begin to brown. Remove Brussel sprouts from grease and place on paper towel to drain. In large bowl, crumble bacon, add Brussel sprouts and vinegar and mix thoroughly.