The bacon donutwich from Goodies Frozen Custard & Treats. (Emily Codik/The Washington Post)

Summer is almost over -- well, at least the long vacations and lazy afternoons at the pool, if not the actual season. So what's the best way to have one last hurrah before the cooler, busier days of fall? Ice cream, naturally. These six outrageous desserts are themselves a reason to celebrate.

And yeah, you might want to share them.

A cookie volcano filled with ice cream inside a waffle bowl at Ice Cream Jubilee. (Becky Krystal/The Washington Post)

Cookie volcano inside a waffle cone at Ice Cream Jubilee

Start by ordering two ice cream flavors, making sure Cookies and Cookie Dough is one of them. Next, ask for them to be served inside the shop's quarter-pound chocolate chip and walnut cookie. (Ideally, the cookie will still be warm and gooey.) Then throw caution to the wind, and upgrade the cookie volcano by requesting it all inside a house-made waffle cone bowl. Say yes to the optional chocolate and caramel sauces. There's no point in being coy about this. $8.85. 301 Water St. SE. 202-863-0727.

The loti with avocado and royal milk tea ice creams from Milk Cult. (Becky Krystal/The Washington Post)

Loti at Milk Cult

These purveyors of unconventional ice cream flavors (Chinese five spice, vegan coconut and kaffir lime) also have an unusual dessert in their repertoire: The loti, a kind of ice cream sandwich by way of Singapore, is served open-faced on milk bread that has been dusted in sugar and blow-torched. The bread is topped with two scoops of ice cream -- the avocado is a cheeky wink to one of today's hottest food trends -- plus sprinkles, chocolate sauce and, um, Fruity Pebbles. It's weird, messy, delicious and fun. $7. Fridays at the USDA Farmers Market, 9 a.m. to 2 p.m. at 12th Street and Independence Avenue SW.

The red velvet donutwich from Goodies Frozen Custard & Treats. (Emily Codik/The Washington Post)

Donutwich at Goodies Frozen Custard & Treats

The vanilla custard from Goodies is luscious enough to stand on its own. Sandwich it between a doughnut? In the immortal words of a certain television uncle: Have mercy. Donutwich varieties include red velvet, apple cinnamon and maple bacon, each drizzled with an accompanying sauce. (You can also customize your sandwich.) All are more than generously sized, so bring friends -- and plenty of napkins. $10. Goodies Frozen Custard & Treats, 150 American Way, National Harbor. Check @mmmgoodies on Twitter for food truck locations.

On Rye's babka ice cream sandwich. (Bonnie S. Benwick/The Washington Post)

Babka ice cream sandwich from On Rye

This dreamy frozen treat comes courtesy of On Rye, a Jewish-style deli that expects to open a Chinatown location by the end of the year. A creation of owner Ilyse Fishman Lerner, the sandwich consists of two slices of the coffee-cake-like bread along with vanilla bean gelato from D.C.'s Dolci Gelati. $6 to $7. On Rye stand outside Suite 210 at Nationals Park; Cappy's Crabs, 828 Upshur St. NW; and Chinatown Coffee, 475 H St. NW.

A peach melba Taco Choco from Paisley Fig at Room 11. (Becky Krystal/The Washington Post)

Taco Choco at Room 11

Room 11's Taco Chocos come around once a month, but they're worth the wait. The hefty frozen treat -- a fancy riff on the Choco Taco -- consists of a taco-shell-shaped waffle cone filled with ice cream and decorated with toppings. Don't expect basic flavors here. Think peach melba, chocolate peanut butter and strawberry lavender. Plus, this dessert is so big it's served with a steak knife for sharing. Lizzy Evelyn of in-house bakery Paisley Fig said this month's flavor will be s'mores, featuring chocolate ice cream with house-made graham cracker cookie bits and toasted marshmallows. Stay tuned on Twitter and Facebook for the announcement of when it will be available, around the end of August. $11. Room 11/Paisley Fig, 3234 11th St. NW. 202-332-3234.

The waffle ice cream sandwich at Pop's SeaBar. (Becky Krystal/The Washington Post)

Waffle ice cream sandwich at Pop's SeaBar

At Pop's SeaBar, two warm and crispy-on-the-outside but chewy-on-the-inside waffles encase a generous serving of chocolate and vanilla ice creams. The contrast in temperatures is lovely, and nothing at all is ruined by the fact that the ice cream will likely begin to melt as you eat it. Silverware: Mandatory. $7.99. Pop's SeaBar, 1817 Columbia Rd. NW. 202-534-3933.

Related items:

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The essential guide to ice cream and frozen desserts around Washington

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