My kids (ages 3 and 6) love fish, particularly sushi or roasted salmon.
Raw veggies - bell peppers, cherry tomatoes.
Broccoli, lightly steamed and then sautéed with a bit of garlic and lemon.
Meatloaf.
More "normal" kid-friendly items- soft bread rolls, pasta, meatballs.
Interestingly, they absolutely hate mashed potatoes. I always thought that would be a kid staple, but they won't touch them. They do like mashed sweet potatoes, though.
Mine also don't really like casseroles or mixed-up foods. They like things that can separated on their plates. I really hope they grow out of this soon.