Cook chorizo in a large skillet over medium heat for 5-7 minutes, crumbling with a spoon, until cooked through.

Drain off any rendered fat from the skillet.

In the same skillet, combine spinach, white beans, red onion, evaporated milk, 1/4 cup parmesan cheese, lemon juice, nutmeg, and pepper with the cooked chorizo.

Transfer the mixture to a greased 2-quart baking dish.

In a small bowl, mix bread crumbs, remaining 1/4 cup parmesan cheese, minced garlic, and melted butter.

Sprinkle the bread crumb mixture over the casserole.

Bake uncovered at 375°F (190°C) for 35 minutes, or until heated through.