Very few veggies are complete proteins. That's why you have to combine them with other veggies or grains to get complete proteins, if you're on a vegan/vegetarian diet.
Red beans and rice are a prime example.
There are two schools of thought on this:
The old school says you have to eat complementary veggies/grains in the same setting, to get all the essential aminos.
The new school says you don't, as long as you eat the right combos of grains and veggies, throughout the day.
I'd go with the old school, personally. That helps because, even for most who consume meat, getting those vegetable proteins saves you a lot of money.
One chicken breast, with an ample amount of black beans and rice, will give you the same amount of protein as two chicken breasts.
