In a large saucepan over medium-high heat, melt the butter.
Add Brussels sprouts and garlic.
Cook until Brussels are golden and crisp on the edges, about 5 minutes.
Add water, cover saucepan with lid, and bring to a simmer. Cook until Brussels are soft, 7-8 minutes.
If any water remains, carefully drain it from the pan.
In a small bowl, whisk together mustard, balsamic vinegar, and honey.
Drizzle over the Brussels, and stir to coat.
Cook uncovered for 1-2 minutes, or until heated through.
Sprinkle with salt & pepper.
Serve!