Select 24 whole peppers. (Refrigerate any remaining peppers in a jar, with brine to cover, for another use.) Cut off and discard the pepper stems. Scoop out the seeds with a small spoon (a measuring teaspoon works well). Rinse the peppers to remove any residual seeds, and set in a colander to drain.

Combine tuna, lemon juice, oil, capers and anchovies (if using) in a medium bowl.

Fill each pepper with about 1 teaspoon of the tuna mixture and place them on a serving plate. (Depending on the size of the peppers, you may not fill all 24.) Grind some pepper over the stuffed peppers.

Bring vinegar to a boil in a very small saucepan and simmer until syrupy and reduced to about 2 teaspoons, 3 to 3 1/2 minutes. Drizzle the syrup over the peppers.

Shopping tip: Look for red and/or green jarred mild (or sweet) cherry peppers near pickles and olives or at the "olive bar" in well-stocked supermarkets and specialty-food stores.

Note: Canned white tuna comes from the large albacore and can be high in mercury content. Chunk light tuna, on the other hand, which comes from smaller fish - skipjack or yellowfin - is best for health-conscious eaters. According to a recent study, canned white tuna samples averaged about 315 percent more mercury than chunk light tuna samples. (The chunk light tunas averaged 0.132 parts per million mercury content, while the white [albacore] tunas averaged 0.412 ppm.)

MAKE AHEAD TIP: Cover and refrigerate stuffed peppers and balsamic syrup separately for up to 4 hours. Drizzle the peppers with the syrup just before serving.