Don't skip browning the ground beef—break it into small pieces and cook in batches over medium-high heat until deeply caramelized, which builds rich, savory flavor that elevates the entire dish.

Choose high-starch potatoes like Russets instead of waxy varieties; they create fluffier, creamier mashed potato topping that bakes up golden and crispy at the edges.

After spreading mashed potatoes on top, use a fork to create texture patterns and rough up the surface, then brush lightly with melted butter for a beautiful golden crust while baking.

Add carrots and onions directly into the beef mixture rather than cooking separately, allowing them to absorb the meat's flavors while their moisture helps create a silky sauce without added liquid.

Let the baked shepherd's pie rest for 5-10 minutes after removing from the oven; this allows the layers to set slightly, making for cleaner, more beautiful portions that hold together perfectly.