You can eat sprouts! When it comes to nutrition and cost, they are the cheapest food that is easily available with the highest amount of nutrition. Sprouts do not get cooked, hence no micro nutrients are lost.
They are also high in Potassium which is usually lost while cooking the food. When you cook the any food, it will lead to loss of lots of nutrients. Even when it comes to proteins, fats and carbs, sprouts have an average of 25 to 30 grams of protein, 350 to 600 calories on per 100 grams intake of mung bean, soybeans, lentils etc. Sprouts are also full lots of soluble and insoluble fibers that are very essential for your body.
Another option that I can suggest you, won’t cost you that much on your pocket is Oatmeal. It is one of the best healthy foods that you can include in your diet. It is quick and healthy breakfast food that has whole grain and plenty of nutrients.