*Ground sausage mince can be used instead. Or ground beef, chicken or turkey. I used grass-fed beef sausages. Replace sausages with bacon if desired.
*For a vegetarian option, omit the sausage.
**Replace mozzarella cheese with cheddar, swiss, parmesan, or your favourite shredded cheese.
TO MAKE AHEAD: Assemble the casserole as directed, cover with plastic wrap and refrigerate overnight, allow it to come to room temperature for 30 minutes before baking.
HOW TO CUSTOMISE: Replace any of the vegetables with your own choices if you wish. Corn, sliced zucchini, diced eggplant, diced potatoes, broccoli or cauliflower florets, etc.