Place water, brown sugar and salt in saucepan; heat to boiling, stirring as needed to dissolve sugar. Remove from heat; let cool. Place catfish fillets in glass dish; pour cooled brine over. Refrigerate for 1 hour. Remove fillets from brine; place on wire rack. Refrigerate uncovered for 1 hour to dry. Place cilantro in blender or food processor; process until smooth, adding half of olive oil. Strain through fine cheesecloth; reserve. Repeat procedure using roasted red pepper. Using syringe, inject first cilantro, then red pepper, infusions into fillets. Refrigerate for 1 hour. Hot smoke lightly, using wood chips of choice; finish in 350 degree F oven. Combine brown sugar and water in saucepan; heat to boiling, stirring to dissolve sugar. Let cool. Brush over fillets. Refrigerate until chilled. Cut into 1/4-in.-thick slices; serve with papaya salsa.