Place a large pan or large skillet onto your stove at medium-high heat.
Drizzle in some olive oil, add the garlic and saute it until it becomes fragrant, which usually takes a couple of minutes.
Add the grass-fed ground beef and cook until brown. Drain the excess liquid and grease.
Mix in the cream cheese, salt, and pepper. Once you’ve combined those ingredients into your pan, stir them until the cream cheese has fully melted, and transfer the mixture to your greased baking dish.
Grab a medium bowl, add the eggs, heavy whipping cream, mustard, and 1 cup of shredded cheddar cheese.
Use an electric mixer and mix it on medium-high until it’s thoroughly combined, then pour the egg mixture on top of the beef mixture that’s already in your casserole dish. Top it off with the remaining shredded cheddar cheese.
Place the casserole dish into the oven, baking until the edges are golden brown, which will take about 15-18 minutes. Once the sides are nice and golden, broil the casserole for 2 minutes then remove it from the oven, allowing it to cool for a few minutes.