1 1/2 cups light mayonnaise $
- Mix mayonnaise, lemon juice, onion and curry powder in a bowl and season with salt and pepper. Cover and chill until ready to serve. (Dip can be made up to 2 days in advance.)
- Prepare a charcoal fire, let burn to a gray ash and set grill 8 to 10 inches from coals. (Or preheat a broiler and set broiling rack 8 inches from heat source.)
- Cut sweet potatoes in half crosswise, then cut each half lengthwise and then into thirds to form fingers. Each potato should yield about 12 pieces. Place fingers in a large bowl, add oil, salt, pepper and cayenne. Toss well to coat.
- Grill or broil fingers, turning often, until partially charred and soft enough to easily penetrate with tip of a knife, about 10 minutes. Remove to a plate and season with salt and pepper. Serve warm with curry dip.