Pressure-rendered chicken fat adds flavor as it drips into your heat source and rises back up as smoke.
This recipe was adapted from Modernist Cuisine's post "For a Great Summer Feast, Cook Ahead, and Bring on the Fat."
Combine and divide equally between two 16-ounce jars. Tighten the lids fully and then unscrew them one quarter turn so that they do not explode.
Place the filled jars on a rack or a trivet in the base of a pressure cooker. Pressure-cook at a gauge pressure of 1 bar/15 psi for 1 ½ hours. Start the timing as soon as full pressure has been reached.
Let the cooker cool, or run tepid water over the rim, to depressurize it. Let the jar contents cool to avoid splattering. Strain the jar contents and discard the solids.
Allow the liquid to settle, and then decant the warm fat. Alternatively, refrigerate it until the fat solidifies, at least 4 hours, and then scoop the clear fat off the top.