To fortify the pap to make it a balanced meal;
You can add palm oil and crayfish or raw egg to the pap and cook for some minutes.

For pap processing; You can either use corn, millet or guinea corn. Do not combine when introducing newly so as to be sure your baby doesn't react to any, you can combine later after allergy have been ruled out. Though it's not advisable nutrition wise to combine since they are all carbohydrates and from the same class of food.
You can also prepare soya bean powder separately to go with the pap