Recipe by: Ed Kasky, Executive Chef at Engine Co. No. 28, Los Angeles Preparation Time: 0:30 FOR THE DRESSING: Place the tomato paste, tamarind pulp, shallot, and vinegar in a blender an mix well. Slowly add the oil a drop at a time at first and then in a slow b steady stream until it is all incorporated. Add the salt. Can be kept in th refrigerator for 1 week. FOR THE ONIONS: Peel and slice one large red onion thick enough so that you can handle the slices and they will not fall apart when you cook them. Rub them with a little olive oil and cook the onions over a charcoal fire or under a hot broiler until soft. (Approximately 5 to 6 minutes per side.) Toss in a bowl with 1-1/2 tablespoons balsamic vinegar so that the slices become single rings. These will keep refrigerated 2 to 3 days. TO ASSEMBLE THE SALAD: Wash and dry one medium handful (about 1 cup) spinach for each portion and toss with enough dressing to coat each leaf, being careful not to over-dres the salad. Arrange the onions over the salad and serve. Always serve salads on chilled plates. CHEF'S NOTE: Tamarind pulp can be purchased at Latin specialty stores.