Start by cooking your choice of ground turkey, chicken, or the mushroom and lentil mix until fully browned and tender.
Prepare the cabbage by boiling it, then drain and press it gently with paper towels to get rid of any extra water.
Include any additional vegetables you prefer, such as bell peppers, carrots, or zucchini, and cook them along with the meat until softened.
Layer the cooked meat, vegetables, and cabbage in a baking dish and sprinkle with your preferred cheese blend.
If preparing in advance, assemble the casserole, cover tightly, and refrigerate for up to 24 hours; add 10-15 minutes to the baking time when ready.
Bake the casserole covered until heated through and the cheese is melted and bubbly, then uncover and bake a few more minutes for a golden top.