Heat the olive oil in a large skillet over medium heat.

If using link sausage, remove it from the casings and discard. Add the sausage to the skillet and cook, breaking the meat apart until it’s no longer pink.

Drain any excess grease and return the pan to the heat.

Stir in the garlic, ½ teaspoon salt, and black pepper. Cook for another 1–2 minutes, then remove from heat.

In a small bowl, combine the ricotta cheese, egg, remaining ½ teaspoon salt, and chopped basil. Mix well and set aside.

Remove the stems from the mushrooms and chop them finely. Set aside.

Lightly coat the bottom of a deep, freezer-safe 33×23 cm pan with 250 ml of marinara sauce.

Lay 4 lasagna sheets over the sauce, slightly overlapping if necessary.

Spread ⅓ of the ricotta mixture over the pasta, followed by ⅓ of the cooked sausage, and then ⅓ of the chopped mushrooms around the edges.

Sprinkle ¼ of both mozzarella and Parmesan, and pour 250 ml of marinara sauce evenly over the top.

Repeat the layering process two more times, ending with 4 lasagna sheets on top.

Pour the remaining marinara over the sheets and sprinkle with the remaining mozzarella and Parmesan.

Coat a large piece of heavy-duty foil with nonstick cooking spray.

Cover the unbaked lasagne tightly with foil, crimping the edges around the pan. Wrap it with one or two additional layers of foil.

Freeze for up to 3–4 months.

When ready to enjoy, allow the lasagne to cool slightly before slicing into squares.

Serve it with a sprinkle of fresh basil over the top.

Pair your lasagne with a crisp green salad dressed in a light vinaigrette, and perhaps some garlic bread on the side.

For drinks, a glass of sparkling water or a light red wine will complement the dish beautifully.