Cookie Dough begins with the friends inside the house when all of a sudden the roof begins to leak. While the friends do what they can to stop the leaks, they eventually realize that there are too many holes to fix so Mr. Herriman and Madame Foster go to the safe in order to check to see their finances to purchase a new roof. However, Madame Foster spent all the money on a safe to put the money in (which wasn't even really gold plated, just gold painted.) The friends try to go about their daily business despite the leaks but when Bloo's meatloaf was so wet he thought it was soup, he wanted to find away to fix the roof. Frankie suggested that they find away to raise the money and Bloo decided to make a lemonade stand, but since it was the middle of winter it was to no avail.
Mac came across Bloo and he explained why Bloo's plan wasn't working. As Bloo was about to give up and go outside, Madame Foster brought out a batch of her special cookies in which a passersby saw and wanted to purchase. Bloo and Mac decided to sell the cookies instead of the lemonade, which resulted in quite a lot of profits. Frankie also came along and purchased many boxes of the cookies, claiming Madame Foster only bakes them once a year and she never gets enough of her cookies. This makes Mac realize that they cannot continue to sell the cookies, but Bloo wants the money for himself so he begins to devise a plan to steal the recipe for himself. He convinces Wilt to help him because the cookies would make people happy, and he manages to convince Eduardo and Coco by giving them a share of the profits.
As Bloo and company begin to try to get to the safe, Bloo sprays a substance which reveals that there are security lasers. Bloo decides to have Eduardo lowered down over the save in a mission impossiblesque fashion, but Coco forgot to bring torchy so they were unable to. Mr. Herriman arrives and when he is about to formally bust Bloo, Bloo makes him an offer that he cannot refuse, to be Chairman of his new cookie company. Mr. Herriman agrees and he opens up the safe, allowing Bloo to get the recipe which allowed Bloo to start backing his cookies. Bloo begins to sell more cookies than they can make, and he forces the other Imaginary Friends to do his bidding without rest or breaks. After a little bit of time, Madame Foster arrives and Bloo formally buys her out by giving her 1000 new roofs and a super chocolate cookie.
Meanwhile, Mac goes outside to open the cookie stand and he finds Frankie there, after speaking with her he realized that she slept outside all night in order to be able to get the cookies as soon as possible. Mac gives Frankie the cookies but when he tries to get some help from her, she blows him off and runs away without saying a word. Bloo, is then seen coming into the house on his brand new boat. As he goes inside, he finds Wilt and Coco taking a break watching TV. He commands them to get back to work and then he summons his new butler to create him a ruby filled, sapphire encrusted pizza with pepperoni. Bloo then goes outside to find Mac in which Mac claims that no customers are coming. Bloo claims Mac doesn't know the fundamentals of business so he begins to go about doing some eccentric things to gather customers.
Bloo forced a customer to purchase a cookie, but when the customer explains that the missing ingredient is love, Bloo and Mac storm into the kitchen. Mac claims Bloo is going to start adding more love, but Bloo says that they merely need to add more extreme elements. From see-through Cookies to septuple chocolate chip cookies, everything Bloo tried to get more customers failed. When Bloo returns to the kitchen he demands that the Imaginary Friends work harder, but informs Eduardo that he can no longer remain on the job because there are not enough profits (yet Bloo shows Eduardo how he could only get a 23K gold statue of himself instead of a 24K gold statue as an example of sacrifice.) When the other friends begin showing discontent, Bloo fires every one of them. Bloo begins to make the cookies on his own, but his inept cookies skills eventually set the cookies on 2500 degrees which causes most of Fosters to burn up in flames. Bloo then returns to his original idea of selling lemonade to make up for the roof which he burned. Mac, Eduardo, Wilt and Coco go there to speak to Bloo, Bloo apologizes and he gives Mac a free glass of lemonade. When Mac asked for a straw, Bloo demanded 10 dollars in which Mac unwillingly paid. As soon as Bloo got the money, Madame Foster came by and took the 10 dollars, reminded Bloo how much he still owed her and told him that she took all of his fancy new equipment such as the crown.