Heat oil in a wok or large frying pan over medium-high heat, then add the garlic, ginger and chili flakes.
Saute for 1 minute, just until fragrant, then stir in the sprouts and stir-fry until tender and browned at the edges, about 5-7 minutes.
Meanwhile, in a small bowl whisk together soy sauce, honey, lemon, gluten free flour and sesame seeds.
Pour the soy mixture over the Brussel sprouts in the hot pan, and cook for 2 more minutes or so, until a thick, sticky sauce is formed.
Serve hot, and enjoy!