Cut each chicken breast across but not all the way through the meat and open the breast up; pound gently and flatten to form large, very thin cutlets. Season the chicken with salt and pepper. Combine the garlic, zest, juice, tarragon and extra-virgin olive oil in a shallow dish and turn the chicken to coat evenly in the mixture. Let marinate 15 minutes.
Heat a griddle or grill pan over medium-high heat. (Alternatively, chicken can be cooked off 1 at a time in a large skillet.) Shake the excess marinade off the chicken and cook 2 to 3 minutes on each side until cooked through and lightly browned. Discard the marinade.
Meanwhile, heat a small skillet or pot over medium heat, melt the butter and add the shallot; cook gently 3 minutes. Sprinkle with the curry powder and stir; whisk in the flour and cook 1 minute more. Then whisk in the broth and bring to a bubble. Add the peas and simmer in the sauce for 2 minutes.
Spoon the gravy into small pools on a platter and top with the chicken. Serve with the Citrus Salad alongside or on top of the chicken.
Citrus Salad with Toasted Seeds and Pine Nuts:
Gently toast the sunflower and sesame seeds with the pine nuts in small pan over medium heat.
Combine the shallot, preserves or honey, Dijon, juice and vinegar. Whisk in the extra-virgin olive oil to emulsify and season with salt and pepper.
Combine the lettuce with the tarragon, orange and grapefruit sections, dress with the seeds and dressing just before serving.