Heat olive oil in a large saute pan that has a lid.
Dice up onion and saute in olive oil until onion is translucent. Add garlic and saute until garlic becomes pale golden in color.
Wash the kale thoroughly, and add it a handful at a time to the pan. Stir until it begins to wilt and all of it can fit in your pan.
Add about a half cup of broth or water, turn the heat down to low-medium and cover the pan.
Season with a pinch of sea salt and ground pepper. Do not leave the pan unattended for too long--set a timer if need be. The goal is to let the kale simmer in a small amount of liquid for ~30 minutes. This will require frequent stirring and the addition of small amounts of liquid to keep the kale from sticking to the pan. The longer you cook it and the more liquid you add, the more tender and delicious the dish will be--however you will lose nutritional value if you cook it too long. Taste it every now and then--when you are happy with it, take it off the heat and enjoy!