Set a large skillet or wok over medium-high heat and add the olive oil and butter.

When the butter is melted, arrange the trimmed green beans in a single layer in the hot pan. Let them cook undisturbed for 3 minutes, giving them time to develop golden brown to brown spots in places but not burn.

Use tongs to turn the green beans and continue cooking for an additional 3 minutes, stirring occasionally but keeping them from overlapping.

Remove the pan from the heat, then add the garlic powder and soy sauce. Toss gently until each bean is lightly coated. Adjust seasoning to taste and serve warm or room temperature.