There are few culinary joys equal to biting into the still-warm crust of a puff pastry tart.

If you have plenty of patience and loads of time, making your own puff pastry is ideal. But for the improvisational cook, a box of good, all-butter puff pastry kept in the freezer is a perfectly legitimate alternative. And, once you’ve learned a few simple rules, the possibilities are vast and easy to riff on.

First, you’ll need to track down a good brand of puff pastry, preferably one made with butter. It’s best to thaw puff pastry slowly — for at least three to six hours in the fridge, where it will keep for a week or so. Avoid the microwave at all costs; it will melt some areas of the pastry into sticky puddles while leaving other parts rigid and frozen.

A flabby, underbaked center is the scourge of puff pastry tarts, and the usual culprits are toppings with a high moisture content or piling on too many ingredients that can steam and ooze all over your dough. A little topping goes a long way, especially when the buttery crust is as much a part of the appeal as whatever is on top.

For sweet tarts, tossing juicy summer fruit with a little cornstarch will bind the liquid and keep it from leaking, but there’s no exact science on what amount you should use. Sliced ripe stone fruit and rhubarb need more, while berries and cherries need a little less.

Sugar amounts are similarly variable. Plan for about 2-5 tablespoons sugar per quart of fruit. Taste fruit before adding the sugar, then wing it.

Whether you go with a savory or sweet tart, be sure to serve it either still slightly warm, or within a few hours of baking. That’s when a puff pastry tart is at its crispest and most-compelling best.

CARAMELIZED SUMMER FRUIT TART

By Melissa Clark

Ingredients:

• 2 tablespoons Demerara sugar, plus more as needed
• 2-5 tablespoons granulated sugar
• 2-3 tablespoons cornstarch
• Pinch of kosher salt
• 4 cups berries, pitted and sliced stone fruit or rhubarb
• 1 tablespoon lemon juice or mild vinegar, such as rice wine vinegar or balsamic
• 1 tablespoon honey, plus more as needed
• 1 tablespoon vanilla extract
• All-purpose flour, for dusting the work surface
• 1 package puff pastry, preferably made with butter
• Whipped cream, crème fraîche or ice cream, for serving

Directions:

Put a rack in the center of the oven and heat oven to 400 degrees. Line a baking sheet with parchment paper. Sprinkle 2 tablespoons Demerara sugar in an approximate 10-by-13-inch rectangle in the center of the liner or paper.

In a large mixing bowl, whisk together granulated sugar, cornstarch and salt. Add fruit, lemon juice, honey and vanilla. Mix well, making sure fruit is coated with the cornstarch mixture. Set aside to macerate while rolling out dough.

On a lightly floured surface, roll the cold puff pastry out to form a 10-by-13-inch rectangle. Transfer the dough to prepared baking sheet, laying it on top of the Demerara sugar. With a sharp knife, lightly score a 3/4-inch border around the edges of the puff pastry. Using a fork, prick the pas try all over inside the border at 1-inch intervals.

Give the fruit another toss to dissolve any honey clumps. Arrange fruit mixture in an even layer on pastry within the border, pouring the juices from the bowl over the top. Sprinkle the top of the tart, including the fruit and pastry borders, with more Demerara sugar.

Bake until the pastry is golden and the fruit is tender, about 30-40 minutes. Transfer the pan to a wire tack to cool for at least 15 minutes before serving. Serve with whipped cream, crème fraîche or ice cream.

Total time: 1 hour, plus cooling; serves 8.

Tips:

Use the lesser amount of sugar for sweet fruit, like blueberries, and add more sugar for tart fruit, like rhubarb, raspberries and tangy varieties of plums. Use 2 tablespoons cornstarch for berries, and 3 tablespoons for juicy fruit, like peaches, nectarines and rhubarb.