Contrary to the comments on the question, I do believe there is a separate answer to this question. However, there is some overlap with regard to the solution the OP may be looking for.
The question hints at the answer. The kids in this case like processed foods.
What do processed foods have?
High sugar and fat content.
The human body is an amazing machine, and it's fueled by fats and carbohydrates. Unlike proteins, which are used as building blocks for our bodies, the other macronutrients are much better sources of energy.
Our bodies are designed to seek out sources of food energy, and our brains reward us for finding them. It's why sugar and fat taste so good. The receptors in our brains evolved to tell us carb-loaded foods were good, because they were rare but helpful for our survival.
It's also been proposed that children, specifically, have higher cravings for sweets and sugars, related to hormone secretion due to bone growth.
So, biologically speaking, junk food is the most rewarding food for a young child's body and brain.
Children will often prefer snacks and junk food, simply because they're hard-wired to, due to the fact that we evolved when such sugar and fat rich food was incredibly scarce.
If they have the option of the junk over healthy food, children will likely choose the junk.
How do you feed your kids healthily, now that they have a taste for processed foods?
The issue isn't really what do kids like, which can be anything with sugar and fat, but how to get them to eat other things. They seem to eat well enough, it's just not the food you want them to eat.
It's going to take some work. The prepackaged and processed foods you rely on will have to go. If your child's brains know that there's an alternative, then their biological imperative is going to be for the other food. This means they'll reject your healthy offerings, throw it up for drama, and whine/complain/throw tantrums until the parents give in.
If those options are removed, you'll likely meet a great deal of push back from the kids and have a lot of stress over the issue. The kids may even try to sneak junk food, or get it from other sources (school, friends). But, if you're consistent and persistent, then eventually they'll realize they have to eat the regular food provided. Their brains should switch from going after the highly rewarding food that's no longer available to just whatever food is available.
That said, there are steps you can take to make the regular food more rewarding. Look for vegetables and fruits that you can add to dishes to make them sweet. Even savory, protein-rich dishes can have sweet sauces added to them to help close the gap between pure processed sugar and natural carbohydrates.
If you want more information about how to get them to eat the other foods, then the "picky eater" questions on this site will be a great help.