Preheat your oven to 425 degrees F and position a rack in the lower third of the oven. This placement helps the cut sides of the sprouts brown against the hot pan rather than just steam from the top heat.

Cook the bacon pieces in a large skillet over medium heat for 4 to 5 minutes, stirring occasionally, until they are browned and starting to crisp but not completely done. They will finish cooking in the oven. Use a slotted spoon to transfer the bacon to a paper towel-lined plate. Pour the bacon drippings into a large mixing bowl and save them.

Add the olive oil, apple cider vinegar, salt, and pepper to the bowl with the bacon drippings. Add the halved Brussels sprouts and sliced shallots and toss everything together until well coated.

Pour the Brussels sprouts mixture onto the baking sheet and spread into a single layer. Arrange as many sprouts as possible cut-side down so the flat face makes full contact with the pan. Scatter the partially cooked bacon pieces over the top.

Roast for 15 minutes without touching them. This is important: letting the sprouts sit undisturbed allows a proper crust to form on the cut side. After 15 minutes, use a spatula to give them a gentle toss and check for browning. Continue roasting for another 8 to 10 minutes until the sprouts are tender when pierced with a fork and the edges are deep golden brown.

Remove the pan from the oven and immediately drizzle the honey evenly over the top. Toss gently to coat and taste for salt. Transfer to a serving dish and serve right away.