Take biscuits out and let them thaw on parchment paper lined cutting board. They should be thawed in about 30 minutes.
Preheat oven to 375 and grease a 9x13 baking dish.
Preheat medium cooking pan and add canola oil.
Add diced onion and saute until transparent.
Add breakfast sausage, break it apart, and cook until it's cooked through. Break apart clumps as sausage cooks.
Cut each biscuit in fours and lay the biscuit quarters in the bottom of the prepared baking dish, in one even layer.
Spread cooked sausage and onion mixture over the biscuits.
In a mixing bowl, whisk eggs, milk, heavy whipping cream, salt, and pepper together until smooth.
Gently pour the egg mixture all over the biscuits and sausage.
Bake for 30-35 minutes until the internal temperature in the center of the casserole reaches 165°.
Note: try serving this breakfast casserole with some sausage gravy.
Video
Notes
Make Ahead:Prepare the casserole up to the baking step. Cover it up with plastic wrap or foil and carefully place it in the refrigerator.You can prepare it the night before and bake it in the morning. Bake time shouldn’t be affected much, may be only by a couple of minutes.When ready, take the casserole out of the fridge and take off the wrap or foil. Let it warm up on the counter for about 30 minutes, then preheat the oven. Bake until it’s raised, golden brown on top and thermometer inserted in the center reads 165°F.