Place the quartered potatoes and peeled garlic in a large saucepan and cover them with water. Bring the water to a boil and cook the potatoes until they are tender.
Drain the potatoes and add the butter, milk, salt, and pepper.
Finish the potatoes by mashing them until they are light and fluffy. Then cover them and set them aside.
Filling Preparation
Begin by frying the diced bacon until it is crispy in a large skillet, over medium heat. After the bacon is done cooking transfer it to a plate, using a slotted spoon, and set it aside.
Add the onion, along with ½ tsp salt and pepper, to the skillet and cook them until they are soft. Add 1 tsp of sugar and continue cooking until the onions are caramelized.
Once the onions are caramelized, stir in 1 pound of ground beef and cook it until browned.
At this point, add the carrots, peas, and garlic and cook until the vegetables begin to soften.
Stir in tomato paste and flour and cook, stirring until well blended.
Stir in the beer and bring it to a boil. Add the cooked bacon, broth, rosemary, thyme, ½ tsp salt, and pepper, and bring back to a boil.
Cooking Instruction
Turn the oven on and preheat it to 350 degrees F. While the oven is heating, continue simmering the filling uncovered to help thicken the sauce, as needed.
Spooning the mixture into 8x8 casserole dish and then top it with potatoes. Place it in the oven and bake for about 35 minutes. The filling should be hot and the potato topping lightly browned.
Remove it from the oven and top with shredded cheddar. Return it to the oven and bake for 10 more minutes.
Remove the dish from the oven and let it rest for 10 to 15 minutes before serving. This allows it to cool and it will hold together better when served.
Recipe Options
You can substitute the beer by using 1 C of red wine.
If you are pressed for time, you could fry the onions with the burger and use 1 bag of mixed vegetables (carrots, peas, corn) in place of fresh vegetables.