Want bigger meals without extra calories? Yes you can eat extra helpings of low calorie foods like salad (as long as you don't add high-calorie toppings), but here are some other tips:

Use smaller plates. Use smaller plates and bowls when serving food -- this will make a smaller meal seem much larger. Putting a single sandwich in the middle of a dinner plate will make it seem wimpy and even if it's enough food, you'll feel like you're being cheated. Put that same sandwich on a lunch plate or even a saucer and it will seem more substantial!

Multiple items. When you prepare a meal, make a whole meal out of it with multiple items: an appetizer, a salad, an entree, a side dish, a bit of fruit, dessert, etc. Even if each of these items is small and the total is within your calorie budget, the net effect of all the different items will be the perception of a much larger meal. I used to just do a couple sandwiches for lunch -- and I'd find myself snacking later, or eating more dessert or nuts or something high calorie because I felt like I hadn't eaten enough. But now I make a lunch that's overall lower in calories but has multiple elements: a sandwich or two, some yogurt or cottage cheese with fruit, a salad, some chocolate chips for dessert, etc. This feels like I'm getting a lot of food and it takes longer to eat, though the reality is it's less calories than my old style lunch!