when shrimp is cooked (nice and pink and barely translucent) remove it to a plate, lower the heat. add the rest of the butter and shake until thickened.
add the shrimp back and keep shaking. If the sauce breaks read note below.
Serve with rice or baguette. Garnish with green onion.
Notes
If the sauce breaks add a little water or an ice cube and shake it back together.If your having a hard time thickening add more butter and shake or mix a little cornstarch and water and mix it in.