Preheat oven to 500 degrees F.
Cut Brussels sprouts length-wise into 1/4 pieces (i.e., cut Brussels sprouts in half, and then in half again).
Cut bacon into ½ inch pieces.
Combine Brussels sprouts with oil, bacon, salt, pepper, and red pepper flake. Place onto a lined baking sheet in a single layer. Spray with additional oil as needed.
Roast Brussels sprouts for 30-35 minutes, turning every 10 minutes to allow even roasting.
When Brussels sprouts have become golden brown and bacon has become crisp, sprinkle minced garlic and splash vinegar evenly onto the sprouts.
Continue to roast for another 5 minutes or until the balsamic vinegar has begun to thicken and become a glaze.
Remove from oven, taste for seasoning, and enjoy!