Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper.
Trim the ends of the brussels sprouts and cut them in half vertically to ensure maximum surface area for browning.
In a medium bowl, toss the sprouts with 1 tsp of olive oil, sea salt, and black pepper until evenly coated.
Spread the sprouts onto the prepared baking sheet in a single layer, ensuring the flat sides are facing down.
Roast the sprouts for 20-25 minutes, tossing halfway through, until the edges are dark golden and crispy.
While the sprouts roast, season the chicken breast with garlic powder and a pinch of salt.
Heat the remaining 1 tsp of olive oil in a stainless steel or cast iron skillet over medium-high heat.
Sear the chicken for 6-7 minutes per side until the internal temperature reaches 165°F and the exterior is golden brown.
In a small saucepan over low heat, whisk the balsamic vinegar and honey together, simmering for 3-5 minutes until the mixture reduces into a thick glaze.
Remove the sprouts from the oven, toss them immediately with the balsamic glaze, and serve alongside the sliced chicken breast topped with crushed pecans.