2) While the chicken is cooking, make the red pepper mayonnaise. Pulse all ingredients in a food processor to blend.
3) Discard poaching liquid and place chicken on a plate to cool. When cooled, shred chicken into large bowl and mix with red pepper mayonnaise. Refrigerate until chilled. Put orange juice into saucepan and boil over medium-high heat until reduced to a syrup. Toast baps and place lettuce leaves on each. Divide chicken mixture evenly on rolls and sprinkle fennel shreds on each. Drizzle orange syrup over top. Garnish with orange slices and fennel fronds.