Prepare the potatoes: Boil potatoes in salted water until tender (about 15 min). Drain and mash with milk, butter, and salt until smooth. Or use my creamy mashed potato using the Thermomix recipe. Cook the filling: Heat oil in a pan over medium heat. Add ground meat and cook until browned. Stir it occasionally to break it up into crumbles, but let it sit long enough to get that nice caramelized crust. This is where the flavors happen. Add finely chopped onions, and minced garlic to the pan. Stir everything together and let it saute until the onions are soft and fragrant. About 5-7 minutes.
Season and deglaze the pan: Sprinkle 1 tsp of salt, 1/2 tsp smoked paprika, and 1/2 tsp of black pepper over the meat. Then add 2 Tbsp of flour. Combine everything and let it cook for about 2 minutes to get rid of that raw flour taste. Next, stir in 2 Tbsp of tomato paste and cook for about 1 minute until it smells rich and toasted. Then deglaze the pan with 1/3 cup of red wine. Or use beef broth if you prefer. As you pour it in, scrape the pan.
Add vegetables and flavor: Stir in frozen mix veggies and let mixture simmer for 4-5 minutes. It should thicken slightly and look rich and hearty. Season to taste.
Assemble the pie: Spread the meat mixture in a baking dish. Top evenly with mashed potatoes, spread gently with a spatula. Use the back of a fork to create crisscross patterns on the surface. Not only does it look fancy, but those ridges get deliciously crispy in the oven. Finally sprinkle with 1 cup of shredded cheese over the potatoes. This is the secret to that golden, cheesy crust everyone loves.
Bake to perfection: Place the dish into a preheated oven of 400F and bake for about 20 minutes. You're looking for the cheese to melt and the mashed potatoes to turn a gorgeous golden brown.
