French Lyonnaise Potatoes are simply skillet fried potatoes with crisp edges, laced with tender, caramelized sweet onions, bathed in plenty of butter and topped with a sprinkle of parsley.
Slice potatoes and onions thinly using a mandoline slicer, or about ¼" thin if slicing with knife.
Heat oil in a large skillet over medium-low heat. Add half the potatoes to the bottom of hot skillet. Sprinkle with about ½ salt and pepper. Top with half the butter. Repeat with second half of potatoes, salt, pepper and butter.
Cook until potatoes begin to brown on the bottom, 10 to 15 minutes. Stir occasionally with flat metal spatula and add a little (about ¼ C) chicken broth as needed as potatoes cook to prevent potatoes from sticking.
Break onions into rings. Add to potatoes with garlic. Stir into potatoes and cook until onions are cooked through and begin to caramelize, approximately another 10 minutes. Add additional broth as needed to keep potatoes from sticking.
Remove from heat. Spoon into serving dish. Garnish with fresh parsley.
Notes
Keep use of broth to a bare minimum. Too much broth will "boil" the potatoes and keep them from browning and becoming crispy.