First determine your size cast iron skillet, or casserole dish. This recipe suits a roughly 12 inch cast iron skillet, so any larger or smaller will require adjustment to the number of listed ingredients.
You'll want to take care of your potatoes first. Wash and peel them, then simmer in boiling water until softened (fork-tender) - this may take up to 30-45 minutes depending on their size.
In the meantime, mince your fresh herbs and garlic, and peel and chop your carrots and onions, then set aside.
Drain and allow potatoes to cool before mashing or running through a potato ricer. With mashed potatoes in a bowl, add the 3/4 cup of heavy cream or milk as well as salt and pepper to taste. Then set aside.
Now preheat the oven to 425F.
In your cast iron skillet, brown the ground beef or lamb. Also add in your chopped onion and diced carrots.
(Optional) When cooked nearly 75%, add in the 1/2 Malbec. This adds an amazing aroma and flavor to the meat, but the alcohol does get cooked out.
Then add in your minced Rosemary, Thyme and garlic, turning down the heat to medium/low. Add the 1 cup of broth and simmer until your carrots are fork tender.
When carrots are tender (if not already previously boiled), turn off the head and add in your sweet peas to the mixture.
Using a spatula, evenly distribute the mixture across the skillet. Then spread your mashed potatoes evenly over top before placing in the oven.
Now you have two choices: cook for 30-40 minutes at 425F, or cook for 25 minutes at 425F then broil the skillet for up to 10 minutes. Broiling will create that charred texture on the potatoes.
Serve and enjoy.