Place the chives in the pitcher of a blender with the olive oil. Blend until smooth.
In a medium bowl, add the chive puree, turkey, shallots, mustard, salt and bell peppers. Using clean hands, blend the mixture together until incorporated. Portion the turkey into 4 large burger patties and place on a tray and refrigerate.
On a hot grill or in a hot saute pan, sear the burgers on each side and then reduce the heat or move the burgers to a cooler spot on the grill, and continue to cook for 10 to 12 minutes. To test for doneness, poke the burgers with a skewer and press down to see if the juices run clear, or a meat thermometer inserted in the center reads 150 degrees F.
Split and toast the buns, and then top each with a burger, a piece of roasted tomato, some watercress and some ranch dressing. Top each with the other half of the buns, then place a large skewer through the burgers and serve!