Preheat the oven to 400F. Make the vinaigrette by shaking all of the ingredients together in a jar until combined and the sugar has dissolved. Taste, and add more fish sauce, vinegar, or sugar to your preference.

Preheat a large ovenproof skillet to medium-high heat with the olive oil. When the oil is hot, add the Brussels in one layer and let them cook undisturbed for about 5 minutes until they start to brown on the bottom.

Shake the pan once to toss the sprouts, then transfer the entire skillet to the oven. Roast the Brussels for 10-15 minutes until tender but not mushy.

While the pan is still very hot, add the cilantro stems and a few tablespoons of the dressing to the skillet. Stir to combine, and taste; add more fish sauce vinaigrette to your preference.

Toss the mint and cilantro leaves with the Brussels sprouts and serve immediately. Enjoy!