Trim the bottom stem from each Brussels sprout, taking care to keep the leaves attached. Slice each sprout in half and set aside.

Add the orange juice, shallot, olive oil, mustard, vinegar, maple syrup, and salt to a food processor. Blend until smooth, then set the sauce aside.

Cook the bacon according to package directions until crisp. Transfer it to paper towels, allow it to cool, then chop into small pieces. Reserve the hot bacon grease in a heatproof container.

Place the same pan over medium-high heat and arrange the Brussels sprouts cut side down. Add 1 to 2 teaspoons of the reserved bacon grease and move the sprouts gently to coat them while keeping the cut sides in contact with the pan.

Cook for about 5 minutes until the cut sides begin to brown. Add the prepared sauce to the pan, then shake the pan by the handle to move the sprouts and coat them quickly. Continue for 1 minute or less, then remove from heat when the desired caramelization is reached.

Toss the Brussels sprouts with the reserved bacon pieces and Parmesan cheese before serving.