Vegetarians can eat a lot of food per meal, for example:

Vegetables: seasonal vegetables such as summer cucumbers cowpeas, etc.

Mushrooms: various types of mushrooms, white fungus, etc.

Soybean products: soybean milk, tofu, etc.

Starch: potatoes, pumpkins, sweet potatoes, etc.

Nuts: peanuts, walnuts, etc.

Fruits: Summer watermelon peaches, etc.