Katie Morford takes lunch seriously, especially when it comes to making lunch for her three daughters, who are entering elementary, middle and high school this year.

"It's a big job to feed kids, and packing a lunch has all these built-in challenges," Morford said. "It has to be to-go, so you have to keep it hot or cold and keep it from getting mushy."

The registered dietician, who lives in San Francisco and writes a family food blog called "Mom's Kitchen Handbook," shares her kid-tested tips and recipes in a new cookbook, "Best Lunch Box Ever."

For busy parents, Morford said the secret to packing a healthy lunch is to think ahead, which means making sure the bread box has enough whole-grain bread and whole-wheat tortillas, the fridge is stocked with eggs and leftover chicken and yogurt, and the produce bin has some cherry tomatoes, peppers and melon.

And then you have to plan some more.

"For me, it was about figuring out what I could do in advance, on the weekend and the night before," she said. "And learning that I could rely on my kids to help."

One of Morford's time-saving tricks is to spin off dinner leftovers like pasta into tasty dishes for the next day's lunchbox, such as "Oodles of Sesame Noodles."

"I will make more of a dinner salad, and then scoop out extra and have them already in those containers," she said. "Or I'll roast an extra chicken or make more brown rice."

On the weekends, Morford spends up to an hour working ahead on preparation, then carves out about five minutes after each dinner to prep and package.

In the morning, while she puts together the entrees — heating up some black beans, topping them with cheese and packing it in a thermos — her kids work on their own side dishes of fruit and vegetables.

"I've found it makes them more invested in the lunch," she said. "And it can be fun and creative."

One of the keys to packing fruit for younger kids is to remove some of the barriers to actually eating it.

"First, I make sure they can open the containers," she said. "Then I'll peel the orange and tangerine. I'll cut the apples and squeeze them with lemon or orange juice so they won't go brown."

If there's a soft fruit like a pear or a peach, you can put it inside a container with a napkin, so it stays intact.

"Little things like that can make a difference," she said. "

As part of the well-rounded meal, Morford and her kids sometimes bake a special snack or a treat together, to make the lunch more interesting. It can be as simple as homemade applesauce or granola.

"In our culture, kids are getting sweets and goodies at every turn, after church and soccer practice and at a school party," she said. "But I want to be able to bake beautiful cookies for kids and put it in their lunchbox."

Occasionally, she packs a few convenience foods, but not as many as her kids would like, and never before reading the label.

"A lot of fruit snacks have a lot of sugar, but you can find ones that are just fruit and juice," she said. "So it's (about) getting to know better choices."

It's helpful to have the right gear to keep the lunch fresh once it gets thrown in the locker. Many kids carry an all-in-one bento box with an insulated case and slot for a cold pack, that all fits together like a puzzle.

"There's a product called PlanetBox that's stainless steel," she said. "It's all one piece, and they bring it home and you wash it."

Since her older children think that style of lunchbox is "uncool," she buys small containers for dressing and dip, medium containers for veggies and fruits, and wax paper bags and sandwich pouches for sandwiches and wraps.

In addition, she stocks small thermoses to keep hot foods hot, good water bottles, reusable or compostable forks and cloth napkins.

The cookbook also offers lists of what to stock in your lunchbox pantry, ideas for do-ahead prep and trouble-shooting tricks for problems like kids "too busy" to eat lunch.

At the end, there's a chapter on after-school snacks such as "Italian Quesadillas," made with provolone and Parmesan cheese, sun-dried tomatoes and spinach, plus whole-wheat flour tortillas.

"It's nice and crispy and delicious," she said.

Staff writer Diane Peterson can be reached at 521-5287 or diane.peterson@pressdemocrat.com.