Many years ago, I had a few things I'd do with diet to grow. These will help you grow, but I never reached a high level in competing, so whatever that's worth.
1. Muscle Milk for breakfast. I'm never hungry in the mornings, adding that meal was huge. Eventually breakfast got bigger, I'd add eggs and toast.
2. A few post workouts
A. I'd drink a build mass, osmo nutrition, 100g carbs/50g protein. Then drive to a local tavern and eat 10 chicken legs, or get a large chicken fried rice. Take a short nap and have dinner.
Another successful routine i did, probably had me at my strongest, post workout would be a 20oz coke on the drive home. Then 1lb of steak and 3-6 eggs, depending on appetite. At the time I was also having some cottage cheese before bed, not much, just a few spoonfuls.
3. Late night meals. PB&J with potato chips and a half gallon of whole milk. Sometimes I'd make that a muscle milk shake. This was very very effective for gaining size.
4. Ice cream. Adding a pint most evenings is something to look forward to, adds calories, and it will help u grow.
5. If I wasn't already, eat dirty. McDonald's, taco bell... whatever, just get it in. Chicken nuggets, pizza, burgers....and add the soda, fills glycogen stores if you've trained properly.
6. All of these "tips" were successful when I was eating 3-4 chicken/ rice/ broccoli meals per day. Then I'd "supplement" my caloric intake, always post workout, with one of these options.
7. Recent option, I snack on beef jerkey throughout the day. It has 20g protein, and I eat it over my 8 hour work shift. Basically just ensuring I have a steady flow of amino. I've had good results with this. I think it's the steady supply, I just take a bite or two every hour.
8. Hard boiled eggs. I get 3 breaks at work. No reason I can't eat one on each break. Sometimes I'll add a spoon of peanut butter to help me feel more full.
I do none of these consistently, and certainly not all of them at the same time. Just a couple of things I cycle through, depending on what I'm hungry for, to add calories.