First combine soy sauce, honey, and 1tbspwater in a small dish.
Now in a large pan or wok heat the butter with the olive oil over medium-high heat.Add the green beans and 1/2 tsp salt to the hot oil and toss with tongs to coat well. This step “blisters” and blackens the green beans initially.
Next, reduce the heat to medium heat and cook, turning the beans occasionally until most are well browned, shrunken, and tender (7-8 mins).Reduce heat to low.Add finely chopped garlic and onion , cook stirring constantly until they get softened and fragrant (15-20 seconds). You can add the red pepper flakes at this point if desired.
Carefully add the soy sauce and water mixture and cook stirring constantly until the liquid reduces to a glaze consistency that coats the beans (30-45 seconds).Put vinegar and honey to it.Add sesame oil to taste.Immediately transfer the beans to a serving dish.Don’t forget to scrape out the sauce to include!
Top with optional sesame seeds to make your sauteed green beans look pretty. Serve warm.