Step 1

Carefully peel the membranes off the kidneys. Slice them in half lengthwise so you preserve the kidney shape. Cut out the hard, white centers of the kidneys with kitchen shears or a paring knife. Soak the kidneys in the milk in the refrigerator for 2 to 3 days. If the milk gets too bloody, change it up to once per day.

Step 2

Rinse off the kidneys and pat them dry with a paper towel. Sprinkle some kosher salt on them.

Step 3

Heat a small frying pan on high for 2 minutes. Add enough grapeseed oil to put a film on the pan. You don't want the oil too deep or everything will spatter all over the place. Heat this oil for 30 seconds to a minute. You want it hot, but not smoking.

Step 4

Place the kidneys cut side down in the hot oil so they are not touching. They will want to curl up, so gently press down on them with a spatula or bacon press. Sear like this for 2 minutes. Turn the kidneys over and sear in the same way for another 2 minutes. Kidneys should still be pink in the middle.

Step 5

Take the kidneys off the heat and allow to rest on a cutting board for 3 minutes. Sprinkle some lemon juice over them. Serve finished with coarse fleur de sel.