Preheat oven to 425° F. Place a cast iron skillet in the oven to preheat (optional).
While oven is heating, prepare the chili sauce. Whisk together all sauce ingredients in a small saucepan and heat over medium low heat, stirring, until thickened. Remove from heat and set aside.
Once oven has preheated, toss brussels sprouts with olive oil and add to hot skillet or a baking dish. Bake for 20-30 minutes, stirring halfway through, until brussels sprouts are crispy and caramelized. Remove from oven and stir in chili sauce. Sprinkle with sesame seeds and additional chili flakes (optional).
Keywords: sweet brussels sprouts, chili brussels sprouts