Rinse 2 cups of dried field corn in cold water. Remove any stones or struggling kernels.
Add 1 tablespoon of calcium hydroxide to 8 cups of water in a non-reactive pot (I used stainless steel). Combine well. Add the corn to this mixture.
Bring to a boil and then reduce heat to a simmer. Cook for 30 minutes or so, stirring occasionally. When the skins of the kernels slip off easily then it's had enough cooking time.
Remove from heat, cover, and let sit overnight at room temperature.
The next day (or at least 6-8 hours later) drain the corn and massage it under running cold water. Use your hands to remove the skins from the kernels. Change the standing water a couple times until it starts to run clear.
Drain the corn and add to a food processor. You'll need 1 teaspoon of salt and approximately 1/2 cup of water for the whole batch (as photographed above I ground it in two batches in a smaller food processor). Wipe down the sides of the food processor occasionally. It will need approximately 4-5 minutes to thoroughly combine, you can add splashes of water if it's not combining well.
Use immediately or cover with plastic/foil and store it in the fridge.
If you want to make tortillas with the masa dough, adding some masa harina to it will make it easier to handle. I added about 1/2 cup to this batch.