Sort through green beans and trim ends if necessary.
Warm butter or ghee in a skillet over low heat.
Add garlic and sauté until fragrant; do not brown.
Add green beans, toss to coat with the butter and garlic, cover and let cook undisturbed for 3-4 minutes. Uncover to stir every 1-2 minutes until the green beans are tender-crisp, about 5-7 minutes total.
Squeeze the fresh lemon juice over the green beans, sprinkle the zest over top, and season to taste with salt and pepper.