Slice the chicken breast into small, bite-sized pieces and season with half of the sea salt and black pepper.
Trim the ends of the Brussels sprouts and cut them in half lengthwise.
Mince the garlic clove and set aside.
Place a large skillet over medium heat and add the diced pancetta, cooking until it becomes crispy and the fat has rendered.
Remove the pancetta with a slotted spoon and set aside on a paper towel, leaving the rendered fat in the skillet.
Add the olive oil to the skillet, then add the chicken pieces and cook for 5-6 minutes until golden brown and fully cooked through.
Remove the chicken from the pan and add the Brussels sprouts, cut-side down, into the remaining oil and fat.
Cook the sprouts undisturbed for 4-5 minutes until the bottoms are deeply caramelized and tender.
Stir in the minced garlic and cook for 1 minute until fragrant.
Add the chicken and pancetta back into the skillet, then drizzle the balsamic glaze over the top.
Toss everything together for 1-2 minutes until the glaze is warm and coats every ingredient.
Season with the remaining salt and pepper before serving.