Preheat your oven to 350 degrees
On medium heat and in a medium to large skillet, preferably a non-stick one, add a small amount of oil or butter. Add your sausage and start browning your sausage and breaking it up as you go.
Once the sausage starts to brown about halfway, start adding spinach. I go a handful at a time. One handful, mix with the browning sausage, and then so on and so forth until the whole bag is in with the sausage. Spinach shrinks up as it cooks.
While the sausage and spinach are marrying in the skillet, add two handfuls of your shredded cheese and mix into your sausage and spinach. Just letting the cheese melt a little before taking it off the heat.
In a bowl (I like using a measuring cup,) crack your six eggs. After cracking, add about a ½ cup of milk to your eggs (makes them fluffy, works with scrambling eggs too,) along with your seasonings. Whisk them together, you can use a whisk or fork. I like using a fork.
In a casserole dish or baking pan, lightly oil your pan.
Add in your sausage-spinach dish before pouring your eggs on top. Top the mixture with 1-2 handfuls of cheese and pop it in the oven.
Bake for about 20 minutes or until the edges are slightly brown.