Go bananas! It's always the right time of year for this frozen treat

I know fans of frozen desserts that will go out in a snowstorm for a scoop of their favorite flavor. If you love ice cream, you'll eat it no matter what the weather is like. So, even though summer is still months away, it's ice cream season now (and always).

The same doesn't always go for ice cream flavors based on fruit. Sure, you can go into the supermarket or a big-chain ice cream shop and get strawberry or cherry ice cream any time of year, even though those flavors depend on late-spring or early-summer fruit. But, for the best homemade fruit-flavored ice cream, I prefer to use fresh, in-season produce.

One particular fruit, though, is reliable virtually any time of year: the banana. Grown in the humid tropics, bananas are always in season and almost never disappoint you; unless, that is, all you can find are green bananas, which will still ripen to brown-speckled yellow skins within three to four days.

I love to use bananas to make ice cream, because the fruit itself has a smooth, creamy consistency already very much like that of the frozen dessert itself. And they become so sweet when fully ripened that you need to add very little sugar to sweeten the ice cream mixture itself. In fact, the bananas even benefit from a hint of sour tanginess from a generous dollop of sour cream to balance out the fruit's sugars

To get the fullest, sweetest banana flavor in the recipe for my banana sour cream ice cream, you must make absolutely certain that you use very ripe bananas; so ripe, in fact, that their skins are uniformly brown, with barely a hint of yellow. Start by buying the ripest-looking bananas you can find in the market. To speed up ripening, detach those you plan to use from whatever bunch you've purchased, and put them in a loosely closed brown paper bag at room temperature. The bag will contain the ethylene gas bananas naturally emit as they ripen, speeding up the process. You can even boost the process by adding to the bag an apple or a tomato, both of which also give off ethylene.

In addition to the sour cream in my recipe, I also enhance the banana flavor by including touches of two other compatible flavors: mellow honey and earthy, slightly astringent walnut extract. The result is a surprisingly complex-tasting yet still mild, even soothing treat.

What could be better? Add to each serving a generous drizzle of my simple bittersweet chocolate sauce. The result is like having a fantastic chocolate-covered frozen banana in a bowl!

BANANA SOUR CREAM ICE CREAM

Makes about 1 1/2 quarts (1/2 L)

8 large egg yolks

1/2 cup (125 mL) sugar

2 cups (500 mL) milk

2 cups (500 mL) heavy cream

1 vanilla bean, carefully split lengthwise with a sharp knife

4 overripe bananas, skins very covered in brown spots

1/4 cup (65 mL) sour cream

2 tablespoons mild honey

1 teaspoon walnut extract

Simple bittersweet chocolate sauce (recipe follows)

In a large mixing bowl, whisk together the egg yolks and sugar.

In a medium saucepan, combine the milk, cream and vanilla bean. Bring to a boil over medium-high heat, then remove from the heat. While whisking the egg yolk-sugar mixture continuously, slowly pour about a third of the hot milk-cream mixture into the yolk mixture. Then, stir in the remaining milk-cream mixture.

Return the mixture to the saucepan and place over low heat. Cook, stirring constantly, until the mixture thickens enough to coat the back of a spoon.

Rest a fine-meshed wire sieve over a large, cold bowl. Pour the hot cream-yolk mixture through the sieve.

In a food processor fitted with the stainless-steel blade, combine peeled bananas, sour cream, honey, and walnut extract. Process until smoothly pureed, stopping as needed to scrape down the bowl. Pulse in a little of the cream-yolk mixture to liquefy the banana mixture; then, stir the banana mixture into the cream-yolk mixture until smooth. Cover the bowl and refrigerate until cold, 1 to 2 hours.

Transfer the mixture to an ice-cream machine and free following the manufacturer's instructions. Serve with simple bittersweet chocolate sauce.

SIMPLE BITTERSWEET CHOCOLATE SAUCE

Makes about 3 cups (750 mL)

2 cups (500 mL) heavy cream

10 ounces (300 g) good-quality bittersweet chocolate, 65 percent to 70 percent cacao, chopped

Pour the cream into a large saucepan and bring just to a boil over medium-high heat, stirring frequently and taking care not to let the cream boil over.

Put the chocolate in a heatproof mixing bowl. Pour the boiling cream over the chocolate. Let stand so the hot cream softens the chocolate, about 1 minute. Carefully stir with a whisk to blend the sauce, carefully scraping down the bowl sides occasionally.

Use the sauce immediately. Transfer any leftover sauce or all of it, if you like, to a covered container and refrigerate for up to several days. Rewarm gently in a double boiler or in a heavy-bottomed saucepan over very low heat.