Not long ago I purchased some wild-caught sushi-quality ahi tuna at my local supermarket. It was a beautiful piece of fish, but my husband and I didn't feel like eating it raw. I brushed it with olive oil and grilled it briefly, and we ate it with fragrant lime wedges, fresh green beans, baked potatoes and a salad of baby greens with tomatoes, cucumbers and peppers. The tuna and vegetables made a tasty, wholesome summertime supper. But something was lacking. Like most Americans, I grew up eating tuna one way. My mother mixed fish from a can with mayonnaise from a jar and usually a little celery, as did my friends' mothers and the cooks at local delicatessens. Even with my flavorful freshly grilled tuna, I missed the mayonnaise. The following day we ate the rest of the tuna with avocado in whole wheat pita. Most people would consider this meal less elegant than the first one, but we liked it better. For me adding avocado was a step in the right direction. Somehow the lean texture of the tuna begs for a thick smooth sauce. Still, for my palate, bottled mayonnaise doesn't complement tuna the way it used to. I prefer mayonnaise's lively French-Spanish cousin known as aioli (in Spain, alioli). Basically, it's made just like mayonnaise, from egg yolks and oil, but it utilizes olive oil instead of vegetable oil, and lemon juice instead of vinegar. Most of all, aioli owes its robust character to fresh garlic (ail in French) added with a generous hand. Aioli is probably the most celebrated sauce of the French Riviera region of Provence. In fact, Jean-Noel Escudier, author of La Veritable Cuisine Provencale et Nicoise, wrote that aioli symbolizes Provence and is the highlight of Friday meals. The custom used to be that on local festivals, the entire village met around an enormous aioli table covered with poached potatoes, carrots, Jerusalem artichokes, globe artichokes, green beans, beets, cauliflower, hard boiled eggs, and poached fish, both salted and fresh. For an even grander affair, there might have been mutton and chickpeas. Josephine Besson, chef-owner of a delightfully homey restaurant called La Mere Besson where I enjoyed dining on a culinary trip to the area, recommends in her book, Ma Cuisine Provencale, serving the garlicky mayonnaise with fish and any vegetables you like, including fennel and sweet potatoes. However, she cautions: "If Monsieur has some aioli, Madame must also eat some; this will prevent a scene on Friday evening!" Irene Borelli, author of La Cuisine Provencale, serves grilled tuna, a popular fish in Provence, with another cousin of mayonnaise, sauce remoulade. Instead of the garlic of aioli, this sauce is accented with shallots, parsley, capers, pickles and anchovies. Like mayonnaise, aioli is made with uncooked eggs, but even old-fashioned French cooks sometimes made their sauce without eggs. Some simply pounded the garlic in a mortar and added olive oil drop by drop, a technique that is also used in a garlic sauce from Lebanon that's often served with grilled chicken. To prevent the sauce from separating, the traditional substitute used by cooks who don't want to use egg yolks is a small peeled baked or boiled starchy potato, which is crushed with the garlic and absorbs some of the oil. An easier method, popular among Americans, is to simply mix prepared mayonnaise with finely minced garlic, lemon juice and a little olive oil. I like to vary the flavor of aioli by adding other fresh ingredients. Fresh hot peppers complement the garlic taste well, as do roasted sweet red peppers. For one of my favorite versions, I use avocado instead of a portion of the eggs. This avocado aioli might make some French people raise their eyebrows, but to me it makes just as much sense as using a potato. TUNA SALAD WITH AVOCADO AIOLI When making aioli, use very fresh garlic that has no brown spots or green sprouts. Avocado colors the aioli a cool green and adds good flavor but if you prefer, you can make the aioli without avocado. If you'd rather omit the egg yolk, puree the avocado with 1â„4 to 1â„2 cup mayonnaise and stir in 1 to 2 tablespoons fresh lemon juice and 1 to 2 tablespoons olive oil, or to taste. You can make this a simple salad of tuna, celery and parsley, and garnish it with thin slices of tomatoes and cucumbers; or dice the tomatoes and cucumbers and mix them with the other ingredients. Sometimes I cook and drain 3 cups of pasta shells and add them to this salad, to make it more substantial. If I don't add pasta, I like the salad with crusty bread or pita or with warm boiled potatoes. 3 large garlic cloves, peeled 1 ripe avocado, preferably Haas, room temperature 1 large egg yolk, room temperature 1 to 2 Tbsp. strained fresh lemon juice Salt and freshly ground pepper to taste 3â„4 cup olive oil, room temperature Cayenne pepper to taste 1â„4 cup slivered almonds (optional) two 185-gr. cans tuna, preferably in olive oil, or 2 cups cooked flaked tuna 1â„3 cup finely diced celery 1 to 2 Tbsp. chopped parsley 1 cucumber, diced 2 tomatoes, diced 1â„3 cup diced oil-packed sun-dried tomatoes (optional) About 16 leaves of tender leafy lettuce Cut off brown end of garlic. Halve garlic cloves lengthwise and remove any green sprouts from center. Halve avocado, remove pit and scoop out pulp. With blade of food processor turning, drop garlic cloves, one at a time, through feed tube and process until finely chopped. Add egg yolk, avocado, 1 tablespoon lemon juice and a pinch of salt and pepper and process until thoroughly blended; scrape bottom and sides of processor container several times. With blade turning, gradually pour in 1â„4 cup oil drop by drop. Scrape down sides of processor. Remaining oil can be poured in a little faster, in a fine stream. Taste; if desired add up to 1 tablespoon lemon juice, 1 teaspoon at a time, processing after each addition. Add cayenne pepper. Taste and adjust seasoning. Transfer to a bowl. If using almonds, preheat oven or toaster oven to 175Âº. Toast almonds on a small baking sheet in oven until light brown, about 4 minutes. Transfer to a plate and cool. Drain tuna and toss with 1â„3 to 1â„2 cup avocado aioli. Add celery, parsley, cucumber, fresh tomatoes and sun-dried tomatoes. To serve, make a bed of lettuce on each of four plates. Spoon salad onto lettuce and sprinkle with almonds. Serve remaining sauce separately. Makes 4 servings. Faye Levy is the author of Fresh from France: Dinner Inspirations.