Have you tried intermittent fasting? There's a lot of controversy around the impacts of fasting, but there's one simple fact involved: it's harder to exceed your calorie needs for a day in 1 or 2 meals than in 3 or more because at some point you are just too full to eat more. If you're focused on getting lots of veggies in your limited meals, the number of calories that "fit in your stomach" will also go down.

Assuming you don't have some metabolic disorders, you'll get used to being hungry for part of the day.