I used to be like you and struggled to consume 3k cals. I am currently bulking on 4600 cals with no issues, here are some tips that helped me!
Try and stick to very dense foods, so you get more calories out of what you can eat! here is a specific list of what has worked for me!
Protein - Drinking raw egg whites (much easier to consume than a chicken breast, especially when eating a cup of brown rice with it!), protein powder
Carbs - Baby food ground brown rice in shakes, ground up oats in shakes, or simply eating liquid protein (As listed above) to leave room for more carbs.
Fats - Olive oil/mct oil/ avocado oil/ other oils (I get 60g fat a day from different oils like olive oil and mct oil which is 80% of my fats or 540 calories), peanut butter (not as good as oils),
When bulking, every night before bed I prepare a shake of 40g protein powder, 20g fats from olive oil, and no carbs. I keep this on my bedside table and drink it when I wake up late at night, this gets in an easy 340 calories (or more with more oil).
I consume the majority of my protein in powder or liquid raw egg whites (pasteurized for safety) so that I can consume large servings of carbs with the meal, such as a cup of brown rice!
Stick to "Fast carbs" such as white bagels post workout, they are more beneficial at this time and easier to get down, I can more easily eat 3 bagels (180g carbs) then I can 1 cup brown rice (140g carbs).
I hope these tips help you out a bit!