01 -
Set your oven to heat up to 350°F (175°C).
02 -
Heat butter in a pan on medium. Cook the onion slices until golden and soft, about 20-25 minutes. Pour in some beef broth, stir, and let it evaporate. Cool them down before using.
03 -
Mix together the ground beef, breadcrumbs, minced garlic, Worcestershire sauce, thyme, mustard, egg, milk, salt, and pepper in a big mixing bowl until it's evenly blended.
04 -
Mix half of the shredded cheese and cooked onions into the meat combo. Form the mixture into a loaf and place it into a baking pan.
05 -
Put the loaf in the oven and bake for an hour, or until a meat thermometer reads 160°F (70°C).
06 -
Spread the rest of the shredded cheese over the top of the cooked loaf, and bake another 5-10 minutes until the cheese melts and looks bubbly.
07 -
Let the meatloaf sit untouched for 10 minutes before cutting it up. Pair it with sides you love.