SMORGASBORD MEXICAN FOOD : The Best Burrito : Johnny’s wins. It’s the cheese--nobody else has it.

No place else in the county has the concentration of ethnic restaurants and delicatessens, fast-food counters and liquor stores, markets and bakeries that there is along Ventura Avenue. Purveyors on the mile-and-a-half stretch of the avenue, from Stanley Avenue to west Main Street, all specialize in Mexican food.

The street, which was the main highway going up to Ojai before the freeway came in, runs along Ventura’s largely Latino westside, past small industrial businesses, oil service companies, deteriorating storefronts and older trailer parks.

This is the perfect place, I thought, to conduct some serious, controlled research into that popular specimen of Mexican cuisine--the burrito.

There had been hope among some of my burrito-loving acquaintances that I would discover the best burrito in some tiny, obscure joint known only to the locals.

But now, I am absolutely prepared to place my right hand on top of a stack of warm flour tortillas and swear that the best burrito is at the well-known Johnny’s Mexican Food--the same place that a friend of mine has long held had the best burrito in town.

There have to be standards when doing this sort of research and that means certain limitations. My criteria had me ignoring the “breakfast” burritos, which I consider to be an American aberration nearly unknown in restaurants in Mexico. Also, I insisted on judging only burritos served where they could be consumed on the premises--even if it was to be at a scruffy outside picnic table.

This section of the avenue has several liquor stores, six markets of various sorts, a bakery, a poker parlor/cafe and one doughnut shop.

There are only six eating places where you can both purchase and eat a hot burrito. All these burritos are made with large flour tortillas. The tortillas are all similar and there is little difference in their quality. Nor does there seem to be much difference in the beans and rice that go into some of the burritos.

Two of these six places are fairly conventional sit-down restaurants. At Maya’s Mexican Food (421 N. Ventura Ave.) they dish out a good, heavy product, filled with rice, beans, green sauce, fresh cilantro and homemade salsa. I enjoyed the tongue burrito ($2.50) that Maya’s makes.

At the other sit-down restaurant, the Tepatitlan Mexican Cafe (362 N. Ventura Ave.), which also bills itself as a taqueria, a chicken burrito ($2.75) I tried had almost no spices and was just plain dull. And the salsa on the side, which can be ordered either in red or green varieties, is weak and watery. This is a place that seems to specialize in some of the more exotic Mexican menu items, such as birria, or young goat and caldo de res-- beef soup.

One of the better burritos on the avenue is at Sandwich Man (1580 N. Ventura Blvd.) where you eat outside in front of a building that looks as though it once was a Foster’s Freeze. This burrito is filled with beans, rice and meat. There’s no salsa inside. But what gives Sandwich Man’s burrito a certain character is the addition of coarsely chopped and cooked onions. The carne asada version ($2.25), although a little saltier than it should be, qualifies as one of the best on the avenue.

If you’re a devotee who likes his tortillas stuffed with only meat, and wants to forget about the rice and beans, then the Gutierrez Drive-In (1001 N. Ventura Ave.) is the place. They cram a lot of the chile verde into their large tortilla. It’s heavy, the meat is shredded--as all burrito meat should be--and it may be the best value of the bunch ($1.90).

Down the street, at Flores Mexican, American Food (880 N. Ventura Ave.) it’s a case of “almost but not quite.” The Flores model ($2) features cubed rather than shredded meat, and that cubed beef, or pork, is sometimes too dry. The fresh cilantro, though nice, is not just compensation for the meat, red sauce and rice and beans with which they fill their tortilla.

Going down the avenue, almost to Main Street, you can tell you’re coming up on Johnny’s Mexican Food (176 N. Ventura Ave.) before you get there. It frequently has a line, especially at lunchtime.

The meat in Johnny’s burritos is cooked with a sauce, and unless you’re ordering a bean or rice burrito, the only food inside the tortilla besides the meat, and the ingredient which I think is what distinguishes Johnny’s, is cheese. No other burrito I tried had cheese. It may be the moisture, the texture or the flavor of the cheese that makes Johnny’s the winner. They use shredded meat, and among the tastiest burritos are the chile relleno mix, chicken or chile verde.

Johnny’s has a very moist, juicy burrito, so remember to ask for a fork at the counter. With a fork, you can politely eat the meat that has fallen out the bottom and onto the paper bag that you’re using as a tablecloth. Johnny’s also has two sizes, the regular burrito ($2) and the smaller one ($1.65).

Now that I know where the avenue’s best burritos hide, I can barely wait to start out next week--on a Taco Tour.