Make the Mashed Potatoes: Peel the potatoes and keep them in cold water until all are peeled and cut. Cut them into small 1 inch size pieces so they cook faster. Put potatoes into a large pot of water (with an strainer insert if you have it). Add 2 tablespoon of Salt to the water. Cover with a lid and bring to a boil (about 8-10 minutes). Boil for 5 minutes or until the potatoes are fork tender.
1 ½ lbs Russet Potatoes, 3 tablespoon Salt
While the potatoes are cooking, chop the parsley, dice the carrots, dice the celery, slice the scallions.
1 tablespoon Italian Flat leaf Parsley, chopped, 3 Carrots, medium, 2 Celery Stalks, 2 Scallions, sliced
Dice the dry-cured chorizo sausage. If using pre-cooked links, remove the casing from the chorizo and break it up into small rough pices with your hands, fork, or knife.
6 oz Spanish Chorizo, dry-cured sausage or pre-cooked links
When the potatoes are soft and slide off the fork or break apart easily, drain the potatoes and add back to the pot for smashing. Add the butter and 1 cup of milk and smash with a potato masher. Add garlic powder, onion powder, ground black pepper, manchego cheese, and parmesan and stir to combine. Taste for seasoning and add a teaspoon of salt or more if needed. Finally stir in a tablespoon of chopped parsley.
1 cup 1% Milk, 1 cup Manchego Cheese, shredded, ¼ cup Parmesan Cheese, grated, 1 teaspoon Ground Black Pepper, 1 teaspoon Garlic Powder, ½ teaspoon Onion Powder, 2 tablespoon Butter, salted
Preheat a large (10-12 inch) skillet or saute pan. Add 2 teaspoon Olive Oil and the carrots and celery. Stir to coat in oil and then spread out into an even layer, cooking for about 4-5 minutes.
2 teaspoon Extra Virgin Olive Oil, 3 Carrots, medium, 2 Celery Stalks
Add the scallions, garlic, beef, and broken up chorizo. Mix everything and cook the beef until it is all browned or cooked through (no longer pink).
2 Scallions, sliced, 2 cloves Garlic, minced, 1 lb Lean Ground Beef, raised w/o antibiotics
While the beef is cooking, make the cornstarch slurry by mixing 2 tablespoon of cornstarch with ¼ cup cold water.
2 tablespoon Cornstarch, ¼ cup Cold Water
Add the salt, pepper, thyme, tomato paste, and Worcestershire Sauce. Mix to combine.
½ teaspoon Ground Black Pepper, ½ teaspoon Thyme, dried, 1 tablespoon Tomato Paste, 1 teaspoon Worcestershire Sauce, 1 teaspoon Salt
Add the chicken broth and the cornstarch slurry. Stir until it starts to thicken, then cover and simmer on low for 8-10 minutes.
1 cup Chicken Broth, 2 tablespoon Cornstarch, ¼ cup Cold Water
Spread the filling out into a 3-quart casserole dish and mix in the corn kernels.
1 cup Corn kernels
Now start to spread the mashed potatoes around the top starting with the outside, spreading the potatoes right up against the side of the dish to seal the edge. Work your way into the center.
At this point, you can store the casserole in the fridge or move on to baking it.