On screen or in real life, meddling moms don't get more neurotically ebullient than Diane Keaton's dessert maven in the regrettable Because I Said So, a half-baked mixture of multi-generational romantic-comedy and vulgar chick flick. Daphne Wilder is a Los Angeles cake-maker and single mother of three grown daughters who's determined not to let her youngest Milly (Mandy Moore) end up like her -- a professionally satisfied, financially secure, fit and attractive but man-less lifestyle matron.

In addition to Milly, there's Maggie the psychiatrist (Lauren Graham) and Mae (Piper Perabo), arguably a borderline nymphomaniac. Their father took off when the girls were little and, while we're supposed to believe that's the source of their insecurities, listening to the endless loop of chirping and needling you really can't blame him. 

The two things on Daphne's mind are new cake recipes and Milly's welfare. With the best of intentions, she tries to micro-manage her allegedly foundering love life. Like mother, like daughter. They're both motor-mouth klutzes and Milly is also in the food business. Her catering company is called Good Enuf to Eat, which may be all some men need to hear before heading for the hills. 

In order to find her child a suitable guy, Daphne resorts to secretly placing an ad on an online dating service and screening the respondents. After the obligatory parade of seventeen geeks and freaks, two promising suitors emerge. Tom Everett Scott plays a suspiciously slick architect and Gabriel Macht is the lounge musician who witnesses Daphne's interviews and throws his retro hat into the ring for Milly, sight unseen.

She "accidentally" meets the two men and decides to test drive both. Despite her thriving business, Milly has ample free time for dating and the predictable complications that ensue. We know the musician is right long before her soufflés rise in his kitchen and she burns them in the architect's soulless modern abode. And not to worry, love is in the offing for Daphne as well. The unlucky guy happens to be the musician's dad (Stephen Collins).

Some may buy into this idea of female empowerment; most will see it for what it is: squirrelly hysteria passing as wisdom and an endorsement of living a sensuously selfish and materialistic life. If empowerment boils down to the right décor, endless shopping trips, and spa-going, Because I Said So is a good manual.

Be advised, mother and daughter's parallel romantic awakenings entail frank sex talk about, for instance, male circumcision and the frequency of female orgasms. In an icky and awkward scene, Milly describes to her mother in detail what an orgasm feels like. Daphne claims never to have had one and if weren't for the mandates of the plot formula would never get another chance. Moore seems as wholesome as any Hollywood actress these days and she and Keaton wear well together, yet even they can't survive such a crassly unfunny and derivative episode. 

The montage-heavy film does calm down after a screechy start that will ruin more than a few date nights. The best part is when Daphne loses her voice and we don't have to hear her prattle on. Laryngitis reminds us Keaton does have a flair for physical comedy. You're inclined to pity her for taking on this role. Obviously when the reviews and box-office numbers came in for her performance opposite Jack Nicholson in the 2004 rom-com Something's Gotta Give, multiple producers ordered up treatments that would take advantage of her status as the new mature sex symbol.

She could have said no of course. Shilling for L'Oreal has to be bringing in a pretty penny. And why not? More power to her. She's still worth it. But Because I Said So goes way beyond hair products and sells something wholly unnatural. Mother doesn't always know best. 

(Released by Universal Pictures and rated “PG-13” for sexual content including dialogue, some mature thematic material and partial nudity.)