Season the non skin-side of the breast with salt and pepper. And pat the skin dry.
Preheat your oven-safe skillet over medium/medium-high heat. Sear the duck breasts skin-side down until brown and crispy, ~10-15 minutes.
While your duck is cooking, bring a pot of water to boil for your noodles, and separately heat the bone broth.
Drain the excess fat from the skillet with the duck breasts.
Finish the duck breasts skin side up in the oven for 5-6 minutes. Internal temperature should read 130F for medium rare. Let them rest for 5 minutes before slicing into half-inch slices.
While the duck is resting (~5 minutes), cook the soba noodles per the package instructions, add the peas to the bone broth, and quickly cook the sliced leek. You can use some of the reserved duck fat.
To assemble, add your noodles to a bowl, pour over the broth with peas and leeks, and top with your roasted duck slices.
You do not need excess oil when searing the duck breast, but if this is your first time making duck breasts, add 1 tablespoon of oil or duck fat before searing. Keep the extra duck fat in the refrigerator and use it in place of butter and oil in your cooking. It's great to fry eggs in, to make popcorn, and so much more!If using frozen peas, make sure they cook for 3 minutes. If using fresh peas, they will need 5 minutes.