Pat the chicken dry with paper towels and lay out on a paper towel–lined tray or plate. Mix the salt, pepper, and red pepper flakes in a small bowl and rub the mixture all over the chicken. Set the chicken aside to dry-cure at room temperature, uncovered, for 30 minutes, or cover loosely with film or foil and refrigerate overnight.
Add the olive oil to the inner pot of the pressure cooker and set to Sauté. Add the chicken, skin side down, and cook until beginning to brown, 8 to 10 minutes; in batches if needed. (Don’t bother flipping; only the skin side needs to render.) Add the shallot, garlic, kale, broth, vinegar, and olives.
Lock on the lid and Pressure Cook on high pressure for 10 minutes. Release the pressure manually. Open the lid and add the butter and optional preserved lemon. Swirl to thicken the sauce slightly.
Serve the chicken on a bed of polenta, noodles, or rice. Spoon the saucy greens, olives, and juices over the top and sprinkle with the herbs and flaky salt.
What’s with the Pits? I love cooking with whole, unpitted olives. But be sure to warn your crowd that the pits are there, especially if there are kids involved. If your crew doesn’t care for the hassle, make this with pitted olives instead.
COOK’S NOTE: Leave the Skin On? Cooking skin-on chicken in a pressure cooker is a nice extra step, if you have the time. You can use the Saute function to brown the chicken, but once you seal the pot, know that the moisture inside prevents the chicken skin from staying crisp. It will still be deeply flavorful, however, with tender, juicy meat. If you want to make things even easier, opt for boneless, skinless pieces here, and skip the step of browning