I hope I don't get slammed for this, and whether it is healthy is arguable.
For a few weeks now I started to eat a hamburger per day. 390 calories. One meal. Substitutes for dinner. No distractions preparing a meal. I eat lots of fruits and vegetables for the rest of the day. Makes me stay within my calorie range so much better than when I tried vegetarian eating. It's just effortless, satisfying. I eat a regular in-n-out burger, with onions, nothing else