The Olsenboye Treat Truck offers up cupcakes and clothing. Brilliant! Photo courtesy of JCPenney

Is there anything the Olsens can't do?

Mary-Kate and Ashley design The Row, consult on Elizabeth & James and are now launching Olsenboye, a new juniors collection sold exclusively at JCPenney.

They have a full-time job trying to dodge the paparazzi, and they even hand out cupcakes from the Olsenboye Treat Truck, seen here in New York City's Union Square.

At the Manhattan preview for Olsenboye, one staffer admitted, "They're the first in the office in the morning and they're the last out the door at night."

That must be why Olsenboye is so spot-on when it comes to teen trends -- these girls know their stuff.

We caught up with the stylish duo to get the DL on the new line.

"The capsule collection shows off our branding on the Olsenboye basics," Mary-Kate told StyleList.

Adding, "We have denim, flannel [and] the studded sweatshirt is a favorite. It has a street vibe."

Sweet ride! The sibs serve up cupcakes onboard the Treat Truck. Photo courtesy of JCPenney

Though it's aimed at juniors, with great graphic tees and layering pieces, the line has broad appeal.

Mary-Kate explains: "It's great that the older customers will be able to enjoy these items too."

While Ashley divulged that her favorite pieces are the plaid flannel shirts embossed with the Olsenboye logo across the back. "It's very downtown," she told us.

The collection hits stores in the New York, Dallas, Los Angeles, Miami and Chicago areas on Nov. 6, but in the meantime you can find us following the Treat Truck for more free cupcakes!

Read more about the Olsen's new line.