Question: how to gain weight for vegetarian diet?
Answer: Nuts and Nut Butters. Nuts are a great source of protein, healthy fats and calories, making them an excellent choice if you're looking to gain weight. ... 
Avocado. Avocados are renowned for their creamy texture and delicious, mild flavor. ... 
Quinoa. ... 
Tahini. ... 
Olive Oil. ... 
Dried Fruit. ... 
Legumes. ... 
Sweet Potatoes.