Start by gathering all your ingredients. Rinse the green beans under cold water and trim off the ends.
In a small bowl, combine the white miso, soy sauce, maple syrup, and sesame oil. Whisk them together until thoroughly blended and smooth.
In a large skillet or wok, heat the avocado oil over medium-high heat until it shimmers slightly.
Add the minced garlic to the pan and stir continuously for about 30 seconds until fragrant but not browned.
Add the trimmed green beans to the pan and stir-fry for about 3-4 minutes until bright green and tender but still crisp.
Reduce the heat slightly and pour your miso sauce over the sautéed green beans. Toss everything together and cook for another minute or two.
Sprinkle toasted sesame seeds over your miso green beans before serving.