Ever use a food blender in place of one of your meals. Should not be so filling with a good quality protein supplement, including eggs or egg powder. Can use a water base, juice or whatever. In any event, sip any protein based drink slowly. Any health drink for that matter.
If wanting to add more calories that use flaxseed oil, pure olive oil, wheat germ oil or safflower oil in the blender. They all have around 500 quality calories in a table spoon. Can learn to pack a lot of nourishment in an 8oz glass. And will be easier to digest liquid than most solid foods. Can also tend to keep the waist size in control, without bloating.
Don't really need 500 grams of protein, most of that will be pissed away. But I'll let you be the judge of what your needs are. 200/250 should be what most trainers require. 4,000 calories should be just about right, depending on body type, age and activity.
Good Luck.