Out of curiosity, how do you get 150g/day of full proteins?

For instance, eating lentils, which is one of the most proteinated vegetable, bring 18g of proteins per 100g, along with 40g of carbs. You also have to eat a comparable amount of cereal to get a full protein chain.

Given that amount of proteins you mention, this requires eating a very large volume of food (cereals and graminacae swell with water during cooking).

I always wondered how vegetarians could reach a highly proteinic diet as a result!