Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   1      cup           fresh orange juice
   2      tablespoons   minced red onion
   2      tablespoons   fresh lime juice
   1      teaspoon      Dijon mustard
   1      teaspoon      ancho chile powder
   1      teaspoon      red wine vinegar
     1/2  cup           olive oil
                        salt -- to taste
                        freshly ground black pepper -- to taste

Preparation:

In a saucepan over high heat, reduce the orange juice until it forms a syrup. Let the syrup cool slightly. In a blender, combine the orange syrup, onion, lime juice, mustard, chile powder, and vinegar. Blend 30 seconds. With the blender running, slowly add the olive oil until the dressing emulsifies. Season to taste with salt and pepper.