Casual Gainer:
One option to consider is 'little and often', that is to say eating less per meal but eating more frequently.
So instead of force eating 2-3k kcal in one instant, maybe splitting that across a few hours.
I used to struggle to eat first thing in the morning, but during a cream gain I found myself needing to eat at this time and started eating relatively small things like pop tarts or microwave pizzas.
I also found myself able to eat 3-4 meals this way and even now I'm still eating breakfast where I didn't before, feeling hungry when I wake up.
Also consider snacking in between, again an easy way to eat more.
I'll try that. It's just I used to eat a hole pizza by my self with little difficulty with little difficulty.
