Tweak the dunk: Oreos go marshmallow crisp and cookie dough

Stack of Oreos
Samantha Okazaki / NBC News

It seems impossible to improve on the Oreo but Nabisco is giving the classic cookie a new twist, launching limited edition "cookie dough" and "marshmallow crispy" flavors.

The cookie dough version uses the standard chocolate wafers and cookie dough-flavor filling with tiny chocolate chips. The marshmallow crispy version, similar to a Rice Krispy treat, uses Golden Oreo wafers to sandwich a marshmallow-flavored filling with crisped rice bits. 

With more flavor comes more calories. One of the new cookies comes in at 80 calories and 6.5 or 6 grams of sugar. That's more than the 53.3 calories and 4.6 grams of sugar of one regular Oreos. The company also recommends you eat fewer of one of the special cookies. The suggested serving size is just two instead of three.

Cookie dough and marshmallow crispy Oreos
Samantha Okazaki / NBC News

The new cookies hit stores February and will be available at Wal-Mart, Target and other major retailers until they run out.

If you can't wait to dunk one of the cookies until then, a secret hashtag will be revealed in an Oreo ad running during the Grammy Awards on Jan. 26. People who watch and quickly tweet the hashtag could win a free shipment of the new cookies.

Based on previous limited edition cookies, these might be available in stores for about six to eight weeks before they're gone, a spokeswoman said.

Aside from regular fixtures like Double Stuf and Golden Oreos, it rolls out limited editions on a fairly regular basis. For its 100th anniversary in 2012, it offered a “birthday cake” flavor, and last year it came out with more than a dozen limited-edition flavors. Last summer saw a "watermelon" Oreo and this past October, "candy corn."