Preheat oven to 400˚F. In a small saucepan, combine the chiles, maple syrup, butter, and apple cider vinegar. Bring to a simmer over medium-high heat, stirring occasionally. Simmer for 2 minutes and remove the chiles with a slotted spoon, reserving them for serving. Continue simmering for an additional 5 minutes, until the glaze thickens a bit.

Spread the Brussels sprouts halves on a parchment-lined baking sheet and brush with the glaze. Transfer to the oven and roast for about 20-25 minutes, basting with the glaze 2-3 times, until crisp on the outside and tender on the inside. Cooking time may vary depending on the size of your sprouts. Serve topped with the reserved jalapeños. Bon appétit!