Position a rack in the bottom third of the oven and preheat to 425 degrees . In a small bowl, mix the peppercorns, coriander seeds, rosemary and sage. In another small bowl, mix three-quarters of the peppercorn mixture with the lemon curd.
In the bottom of a roasting pan, toss the carrots with the oil; season with salt and pepper. Place the chicken on a rack over the carrots. Using your fingers, gently separate the skin from the breast meat. Spoon the lemon curd mixture under the skin and, using your fingers, spread it evenly over the breast meat. Using kitchen twine, tie the ends of the drumsticks together. Sprinkle the remaining peppercorn mixture over the chicken; season with salt.
Roast the chicken and carrots 30 minutes. Reduce the oven temperature to 350 degrees and continue roasting until an instant-read thermometer inserted into the chicken thigh registers 165 degrees , 45 minutes to 1 hour. Transfer the chicken to a cutting board; let rest 10 minutes. Carve the chicken; serve with the carrots.