Picnic to-do lists should always include the following instructions: Dig out 9-by-13 pan.

Bars — also known by their non-Midwestern name, squares — are ideal picnic fare for so many reasons.

First, ease. Who wants to spend a lot of time in the kitchen when the weather is this glorious? Bars can be some of the quickest and easiest ways to pull together a home-baked dessert.

The rectangular baking pan is a particularly useful tool when meals are on the go. After all, dessert now comes in its own handy carrier.

They’ve got a convenient cookie-like portability, too, without all the fuss of actually making cookies. Once they’re cut, bars are generally sturdy enough to be enjoyed without plates or forks.

Bars also have the hit-the-sweet-spot thing down to an art form.

Sure, they’re familiar chocolate-delivery vehicles. But instead of brownies, think about turning to blondies, each butterscotchy bite packed with bittersweet chocolate chunks. Or consider brightening up that classic chocolate-and-nuts combination with a jolt of locally sourced honey.

But bars can also be eloquent showcases for just-picked berries and fruits.

Blueberries? Cherries? Absolutely. Hand me that 9-by-13 pan, pronto.