Follow these detailed steps to create your Ghostly Mashed Potato Bowls. We’ll build the dish in two main parts: creating the rich, savory filling and then whipping up the perfect, pipeable mashed potatoes for our ghostly topping.

Part 1: Crafting the Savory Beef Filling

1. Sauté the Aromatics: Place a large skillet or Dutch oven over medium-high heat and add the olive oil. Once the oil shimmers, add the finely chopped yellow onion. Sauté for 5-7 minutes, stirring occasionally, until the onion becomes soft, translucent, and slightly golden. This process builds the first and most important layer of flavor. Add the minced garlic and cook for another minute until fragrant, being careful not to let it burn.
2. Brown the Beef: Add the lean ground beef to the skillet with the onions and garlic. Use a wooden spoon or spatula to break the meat apart. Cook, stirring frequently, until the beef is fully browned and no pink remains. This should take about 8-10 minutes. Draining any excess fat at this stage is optional but recommended if you prefer a leaner base.
3. Create the Sauce: Pour the beef broth into the skillet, using your spoon to scrape up any browned bits from the bottom of the pan—this is called deglazing, and it’s where a ton of flavor is hiding! Stir in the Worcestershire sauce, dried thyme, salt, and black pepper.
4. Simmer and Thicken: Bring the mixture to a gentle boil, then reduce the heat to low. Let it simmer for 10-15 minutes, uncovered. This allows the flavors to meld together and the sauce to reduce and thicken slightly, creating a rich, hearty consistency that isn’t watery.
5. Add the Vegetables: Stir in the frozen mixed vegetables. Continue to cook for another 5 minutes, or until the vegetables are heated through. Taste the filling one last time and adjust the seasoning with more salt and pepper if needed. Once done, remove the skillet from the heat and set it aside while you prepare the potatoes.

Part 2: Summoning the Mashed Potato Ghosts

1. Boil the Potatoes: Place the peeled and quartered Russet potatoes into a large pot. Cover them with cold, salted water, ensuring the water level is about an inch above the potatoes. Starting with cold water helps the potatoes cook more evenly. Bring the pot to a boil over high heat, then reduce the heat to a steady simmer. Cook for 15-20 minutes, or until the potatoes are very tender. You should be able to easily pierce them with a fork with no resistance.
2. Prepare for Mashing: While the potatoes are boiling, warm the whole milk in a small saucepan or in the microwave. Having the milk warm is key to achieving a creamy, non-gummy texture.
3. Drain and Dry the Potatoes: Once the potatoes are fork-tender, drain them thoroughly in a colander. Return the empty pot to the warm burner for a minute and add the drained potatoes back in. Let them sit for 1-2 minutes, shaking the pot gently. This allows any excess moisture to evaporate, which is the secret to fluffy, not watery, mashed potatoes.
4. Mash to Perfection: Mash the potatoes using your preferred method. A potato ricer or food mill will give you the smoothest, lump-free result, which is ideal for piping. A hand masher also works well for a slightly more rustic texture. Add the room temperature butter and mash until it’s fully incorporated.
5. Add Liquids and Season: Gradually pour in the warmed milk while continuing to mash or stir, stopping when you reach a creamy, smooth, but still firm consistency. You want the potatoes to be soft enough to pipe but stiff enough to hold their shape. Stir in the salt and white pepper. Taste and adjust seasoning as necessary.

Part 3: Assembling the Ghostly Bowls

1. Prepare for Piping: Let the mashed potatoes cool for a few minutes so they are easier to handle. Transfer the mashed potatoes to a large piping bag fitted with a large, round tip (like a Wilton 1A or 2A). If you don’t have a piping bag, you can use a large zip-top bag and snip off one of the bottom corners.
2. Assemble the Bowls: Divide the warm beef filling evenly among four to six individual serving bowls.
3. Pipe the Ghosts: Hold the piping bag vertically over the center of the beef filling in one of the bowls. Squeeze the bag with firm, steady pressure, starting with a wide base and pulling upwards to create a classic ghost shape, tapering as you go. Release the pressure and pull the bag away to create a little peak at the top. Repeat for all the bowls.
4. Add the Eyes: Carefully place two black peppercorns or tiny pieces of black olive onto each mashed potato ghost to create the eyes. Your spooky creations are now complete! Serve immediately while warm.