(NOTE: Use gloves at all times when handling Habanero chiles. Do not rub skin, face, eyes or lips while handling chiles. To reuse gloves, wash thoroughly with soap and water.)
Plunge Habanero chile into boiling water; cover and let stand 10 minutes until softened. In a medium bowl stir together tomatoes, onion, cilantro, and salt. Using gloves, drain chile and trim off stem. Slit chile lengthwise and remove seeds if desired. Mince chile finely. Place chile along with tomato mixture in food processor or blender. Cover and process with several on-off motions until mixture is finely chopped, but not pureed. Cover and chill until needed.