Preheat the oven to 450 degrees.
To prepare the potatoes you need to own a razor-sharp knife to either slice them as thin as possible or use a mandolin for slicing. I like to cut long ways where the surface area of the potatoes is wider. Slice the blue potatoes thin as well.
On the stovetop, begin to heat up the cast iron pan. I grease the whole thing with butter including the sides and then I cut the stick of butter in half (1/4 c) and let it melt onto the pan.
Remove the pan from the heat and start placing slices of potato down, going around in a circle. I like to add in a blue potato here and there for color, but the majority of the potatoes need to be russet potato slices (which are high in starch), so the cake will form correctly.
After getting 1-2 layers down, salt and pepper the cake and sprinkle on the cheese. Add a couple knobs of butter about the size of a pea over the surface of the potatoes. Continue placing potatoes down in a circle for another 2 rotations. Salt and pepper lightly again.
Return the pan to the stove and begin to heat on medium heat for about 4-5 min. You will be able to hear the butter sizzling, and the potatoes that are laying flat on the skillet cooking and getting golden brown.
Without moving anything in the pan, use an oven mitt to place the entire thing on the second rack of the oven as far in the back as you can get it. Close the door. Cook 40 min.
Check the tenderness of the potatoes by inserting a knife to make sure they are soft, if they aren’t, return to the oven for another 5-10 minutes.
When the potatoes are cooked, go around the edge of the “cake” with a knife to free it from the pan. Let cool for 10 minutes.
Place a cutting board on top of the cast iron skillet and flip the cake onto it. It should come out clean and easy.
Chipotle Crema: In a bowl whisk the ingredients together and allow it to sit until it becomes pink. Taste for seasoning. Chill.
Cut into slices like a pizza and serve with chipotle crema and minced fresh chives.