BELIEVE IT, it's hot! If you can't stand the heat get into the kitchen. At least there's a refrigerator in it.

We know the time and temperature for boiling an egg, for baking a cake, for deep-frying everything from a potato to a shrimp. But how many days of sizzling at 95 degrees does it take to fry a brain?

We've heard through the sun-baked haze that the French are so prostrated by the heat they are practicing southern hospitality as far north as the Belgian border. They are reported to be acting, contrary to stereotype, as if they like Americans this summer.

But there's more startling news. No sooner did we try to ice down our suffering digestive systems than we were told the equivalent of: Waiter, there's a soybean in my ice cream. Tofutti has come to Washington.

With that we decided to ride with the heat wave, to present a bazaar of the bizarre. If you keep it around until winter perhaps you will no longer believe any of it, but you can use it as kindling in your fireplace.

An old summertime tradition suggests we Think Christmas as a way to cool July. But when we tried this, we discovered that this Christmas fast food will be peddled as kiddie chic. Mattel is about to market a Barbie Loves McDonald's playset, and Barbie and Ken will be wearing McD uniforms. We'll stick to lemonade and bathing suits as long as we can.

Once cookbook author Julia Child made cooking big box office on television, it was obvious nobody was going to let her keep the field to herself. But who would have expected big box-office television itself to turn to cooking? It won't compete with "Mastering the Art of French Cooking" but there's plenty of sizzle in "The Love in the Afternoon Cookbook" (Evans, $7.95). Not only does it have recipes from the stars of "Ryan's Hope," "All My Children," "One Life to Live," and "General Hospital," there's a come-hither cover of the stars cooking in evening dress or less. If that's the generalists' "Joy Of Cooking" TV-style, for specialists there is the "Days of Our Lives Celebrity Cookbook" (Juvenile Diabetes Foundation International, 1099 13th St. NW, D.C. 20007. $10), which reveals Stuart Whyland's Ziti al Forno and Dr. Greg Peters' mustard dip for raw veggies, and also lists the calorie counts of the recipes so that aspiring stars can keep their television-trim figures.

Surely you know people who drive to distant suburbs to buy their special brand of soy sauce, or go out of their way to a particular liquor store not for its beaujolais but because it has what they consider the only olive oil one should use. Aha, now you've got them: Express disgust the next time you catch them cooking their hand-cut semolina pasta in plain old tap water. The Water Quality Association says it's got to be softened water, rid of the impurities picked up in our defiled atmosphere, for optimal texture and flavor in the noodles. Nobody has yet suggested the water should be imported, but certainly anyone who poaches his salmon in champagne could be convinced to boil his tortellini in Ferrarelle.

Now that there's tofu in your ice cream, get ready for fish in your hot dogs. This week the USDA is gathering petitions on the subject and is considering the prospect of allowing 15 percent fish in your franks.

Maybe you just thought they were out of fashion, but pink peppercorns were out of stock because they were considered dangerous. Well, forget that, and go back to worrying only about their stylishness. The FDA has declared pink peppercorns safe, at least those from the French island of Re'union, which is the only place the beautiful people would buy them from anyway. Just don't try to eat the potentially hazardous pink berries from the Brazilian pepper tree or from Florida, but then you're only likely to find them on trees rather than in spice bottles. So your only real concern is whether you are ever going to find another recipe for pink peppercorns now that you can get them again.

One way people have traditionally tried to slim themselves enough to fit into their designer jeans was by eating that lunchbox standby, tuna. Who could not have predicted, if pressed, that the next step would be designer tuna? It comes from Bumble Bee and is wrapped in a regal label of understated beige with burgundy and gold script. It is called Limited Catch, though we could not find evidence that each can was signed and numbered. Like any limited edition, it costs a premium-- $1.99 at the Georgetown Safeway (where else would one dare to buy haute tuna?) versus $1.49 for Bumble Bee's Chunk White, 98 cents for Chunk Light. It does weigh 1/2 ounce more than the others, and for some unfathomable reason has a whole lot more calories (540 versus 400 for Chunk White and 480 for Chunk Light). Though it sells at a premium price, it is packed not in elegant olive oil as are most premium tunas, but in the same old soybean oil--and vegetable broth, hydrolized protein and salt with added pyrophosphate--as the lesser catches. The difference is in the cut--a handsome whole fillet rather than all or partly flaked--and in the paler color. What our tasters thought of the three tunas--tasted blind--was that the Limited Catch was just plain bland; they'd save their money and calories on the everyday version.

Just as tasters have their favorite tuna and soap stars have their favorite recipes, food sections have their favorite mail. Here's ours:

* From the Roundtable restaurant, after our story on thievery in restaurants, a twin of a kidnaped rubber plant appeared at its doorstep with this poem attached:

"When I was young and foolish

I played a dirty trick . . .

Now that I'm old and wise

I want to change things quick!!!

The purpose of this plant

The reason it is sent

To fill the empty corner

I guess it wasn't lent???!!!"

* From the lawyer who doggedly tracks down and warns violators of the trademark of Derby Pie, a busman's holiday in jest. Wrote attorney Robert A. Donald III from Louisville, Ky., after reading an Express Lane column on Afghan eggplant which was reprinted in his local paper:

"In the enclosure, an article written by you appeared in our newspaper. It purports to be a recipe for eggplant.

"However, this is to advise you that I represent a Nomadic Stripper who calls herself The Afghan Dish . Her "review" has been trademarked, and she has asked me to put you on notice to never again refer (in your reviews) to eggplant which may bear her trademarked act!!!"

What is more natural to follow shopping mall "outdoor" cafes than indoor street food? The streets in this case are movie aisles, where carts are rolling up and down with intermission snacks. The most ambitious to date was spotted at the KB Cinema theater on Wisconsin Avenue. Instant nachos were being served from a cart that had an electric warmer for the melted cheese, the whole mess (which is what it became on the floor when the snacks were discarded) being served in a clear plastic container with one compartment for chips, the other for cheese dip.

One rule that applies as well to food as to the rest of life is that nothing stays simple. Take, for example, Haagen-Dazs ice cream, which may have hit more digits than most in its prices but not in the number of flavors. Now--shades of Bob's and Steve's and all those other first-name brands that have a multitude of flavors--Haagen-Dazs is making Cookies and Cream, Vanilla Swiss Almond and Hazelnut Praline, as well as returning peach to the market. So far they are just at the dipping stores; in the meantime, we're holding our breath for Pink Bubble Gum.

We won't have to hold our breath long to find Haagen-Dazs on every corner. It's been bought by Pillsbury, which plans to increase the ice cream company's growth 25 to 35 percent annually, adding a new plant and opening 150 franchise units a year as well as company stores. Now there are 244 stores and about $60 million sales.

First there were hikers and campers. And breakfast eaters. And health-food enthusiasts. And cake-mix bakers. And candy bar nibblers.

Now they have all been blended into one, at least in the world of food marketing. Betty Crocker is manufacturing a granola bar mix for people who want to save time, feel healthy, get quick energy, eschew preservatives, go natural and satisfy a sweet tooth all at once. No room for the anti-cholesterol movement here, though; the box directs: "Add butter."

Finally, the bizarre becomes commonplace. It is no longer a surprise to find a househusband in the kitchen, and if men once tended to huddle only around the barbecue they now frequently gather around the food processor and microwave. So Miya Gallery at Lansburgh's Cultural Center, 420 7th St. NW, had a wide field for its "Men Who Cook" cookbook. Nevertheless, its publication is cause for celebration, and the gallery is doing so today, 1 to 4 p.m., at a book party with samples to taste from this literary endeavor. Donation of $7 is required for admission, and the cooks will be on hand to sell and autograph the books.