boil spaghetti or whatever kind of pasta you like in boiling water, add a little bit of oil and salt to the water

after its cooked, remove to spaghetti from the hot water. take a pan and put in the butter

put in the onion and garlic(i chopped the garlic in some pretty big chunks so it wont burn if i saute it together with the onion) until the onion and garlic are golden brown

put in the shrimp and wait for it until it changes its color to white or light pink

add in the green beans

add water to the pan. then in a bowl, mix the corn flour with some water. add into the pan while stiring it. add salt and pepper

let it boil then put in the spaghetti and mix it until the spaghetti is all coated with the sauce

or you can just put the spaghetti in a plate then put the sauce, shrimp and green beans on top