I had the same problem as you, along with weightlifting, food is equally important. I am in the same basket as you, I eat 5 times a day with the following:
-Protein (20-50g per meal, example: Cottage cheese, yogurt, chicken, egg whites, protein powder)
-Good carbs every meal (ex: Sweet Potatoes, whole wheat bread, brown rice, beans)
-1-2 servings of veggies per meal (You can have as many as you want really, I don't think you can overdose on veggies)
-Healthy Fats (ex: Nuts, eggs, Peanut Butter, Avocado, olive oil, coconut oil)
-Fruits (only 3 servings per day, breakfast, lunch and supper...no more, because of sugar)
I have been doing this plan for 2 years and I have gained almost 20 lbs