My roommate and I are having an argument over which is better, and what the difference is. Health issues aside, I think boiling turns out vegetables that taste better and steaming makes vegetables limp and soggy. He says the opposite. Who is right?
Either, just don't cook too long!
Only the English boil vegetables---for two days at a minimum---just to be sure that they are hammered to death and all the dangerous vitamins are removed.
I think they are about the same, but steaming is sometimes said to be better as more vitamins will stay. I prefer steaming to boiling in general.
I do as most restaurants do ... quickly blanche then ice bath, drain and hold until needed and the sautée. This method preserves both taste and color and since it is pre-prepped your final cooking time is reduced.
Vegetables come out limp and soggy when they're overcooked, regardless of the cooking method! If boiling, I quickly blanch my veggies just until they are bright green (or whatever color the veggie is), are easy to chew, and still have a nice snap (bite) to them. Steaming is great because you use less water. Either method is great for quickly cooking vegetables, but I prefer roasting my vegetables with just a touch of oil and salt to get that deep caramelization.