A typical balanced meal is a bean, a grain and a vegetable.
Grains are carb-heavy and if whole grain the protein complements beans. (Research is ambiguous on whether this is important). Quinoa stands out as a protein-rich grain that has a complete complement on its own.
Beans are protein-heavy, especially soy.
Dark leafy green vegetables taste good and include micronutrients.
Consider high-protein vegan foods instead of beans.
Most are soy: tofu, tempeh, and other artificial processed soy products.
The other high-protein food is seitan, which is wheat gluten, which is protein. This is often a meat substitute.
Root vegetables and squashes have lots of carbs.
They substitute, or complement, grains in a meal.
Beans are culinarily diverse.
There are: black beans, red beans, pinto beans, garbanzo beans (chickpeas), edamame (soy beans), lima beans, black-eyed beans, pink beans lentils, and many more. There are recipes to cook these in a huge variety of culinary traditions.
Vegan diets tend to be high fat.
Olive oil or coconut oil is used in cooking. Coconut milk is used in curries (Indian or Thai cuisine) and is very high saturated fat. Nuts are frequently cooked with and make a snack on their own. They are very high fat (e.g. peanut butter).
Dark leafy greens are high in micronutrients, but otherwise less essential than you would think.
If you are a lazy bachelor trying to get by on 15 minutes of cooking a day, you can skip the vegetable most of the time if you are meeting your micronutrient needs. You probably want to take a vegan multivitamin anyway since B12 and D are essential.