One cup of chopped onion = 11 carbs or 10 net carbs (subtracting the 1 fiber carb)
We love onions so just make adjustments for them.
I don't actually watch carbs in my diet, I just cut out bread, rice, potatoes, and such starches (i.e. refined carbs). My carbs are quite rude.;-)
I get all my carbs from vegetables and legumes (and, ahem, beer).
Has the same effect on weight loss in my experience..