Wash the spinach well in cold water to remove any sand or grit.

Spin it dry in a salad spinner, or let air drain until nearly dry. Leaving a little water on the leaves is fine.

In a very large pot, heat the olive oil and sauté the garlic over medium heat for about 1 minute. Make sure that the garlic does not brown.

Add the spinach, the salt, and pepper to the pot, tossing to coat the leaves with the oil.

Cover the pot and let it steam for a couple of minutes - but not too long - you don't want it to lose it's deep green color.

Uncover the pot, turn the heat up and cook the spinach for another minute or so, stirring until all the spinach is wilted.

Remove from heat. Using tongs or a slotted spoon, remove the spinach to a serving dish. Top with butter, a little fresh lemon juice and a pinch of kosher salt.