Bring a large pot of salted water to a boil and cook lasagna noodles until al dente (about 7–9 minutes, or according to package instructions). Drain, rinse with cold water and pat dry.

Sauté the fresh spinach in butter (or oil) until wilted, then drain very well to remove excess liquid.

Preheat oven to 375°F (190°C). In a 9×11-inch glass baking pan, spread a thin coat of meat sauce over the bottom.

Add one layer of lasagna noodles (fit about 4 across and use a noodle piece to cover any gap).

Top the noodle layer with half the sautéed spinach, half the cottage cheese (try not to add excess liquid), 1/2 cup of meat sauce and about 1/4 pound of grated mozzarella.

Add a second layer of noodles and repeat with the remaining spinach, cottage cheese, 1/2 cup meat sauce and another 1/4 pound mozzarella.

Add a final layer of noodles, spread the remaining meat sauce over the top and cover with the remaining grated mozzarella (use plenty of cheese).

Bake at 375°F (190°C) for about 30 minutes, or until the cheese is melted and starts to brown.

Remove from oven and let the lasagna sit for 10 minutes before slicing and serving.