Preheat oven to 220β/Fan 200β/425β. Lightly grease a large baking sheet, set aside.
In a large bowl, combine the Brussels sprouts, olive oil, minced garlic, sea salt and pepper. Stir until ingredients are evenly distributed.
Evenly spread the oiled and seasoned Brussels sprouts onto the prepared baking sheet.
Sprinkle the diced bacon evenly around the sprouts on the baking sheet. Make sure everything is in a single, even layer.
Roast in the preheated oven for 20 minutes, stirring once halfway through. (NOTE: The size of your Brussels sprouts will affect roasting time. I prefer small sprouts for better flavor, but if using large sprouts, you may need to roast longer than 20 minutes).
While the Brussels are roasting, mix together the mustard and honey.
After 20 minutes, or when the Brussels and bacon are starting to brown, remove the baking pan from the oven and drizzle the honey mustard mixture over the Brussels and bacon.
Stir until evenly distributed and spread mixture in an even layer on the baking sheet.
Return to oven and roast again for 5-10 minutes (remember, the size of your sprouts will determine this β check at 5 minutes), or until the sauce has thickened and coated the sprouts and the sprouts/bacon are browned.
Remove from oven and stir the mixture to ensure nothing sticks to the pan.
Serve warm.