Green beans with lemon zest and bitters

1-1/2 lb green beans, trimmed
2 T olive oil
3-4 cloves garlic, sliced
1 t finely grated lemon zest
1/4 t Angostura bitters
3/4 t salt
1/4 t black pepper

Steam beans until crisp-tender and drain well. Heat oil in a heavy skillet and saute the garlic for a minute. Add the beans, zest, bitters, salt, and pepper and cook for about 2 minutes.