Increase caloric density, decrease volume. Decrease fiber, raw foods, and protein. Chew more. Don't drink as many liquids during a meal. Eat slower.
Recovering on a more unprocessed diet (like whole food, plant-based) can make one feel very stuffed. It was hard on my stomach to try to gain weight on many vegetables and fibrous foods.
I only gained weight and started feeling less stuffed once I cut out raw food and cut down on vegetables significantly. I ate white instead of brown rice. I had nut butter and some oil instead of chewing through nuts.
The body uses energy to digest. Make it easier for yourself when gaining weight by eating more processed food. You don't have to eat junk food - what this means is eating food that has been mechanically processed some more.
People with anorexia tend to experience lots of bloating. Their stomachs may have shrunk and the body doesn't have as much energy for digestion. As Dr. Shan Guisinger's work explains, they also feel full much sooner than most people due to brain changes.
The feeling of being too stuffed will go down over time as you increase in weight and health. I promise that - at one point I thought I'd never feel comfortable after eating, but now my digestion is fine and meals feel like they're at a reasonable quantity.