Beans on Toast

Ingredients

• extra-virgin olive oil
• sweet or hot Italian sausage, casings removed
• garlic cloves, 3 thinly sliced, 2 finely grated
• dried oregano
• crushed red pepper flakes
• can crushed tomatoes
• kosher salt, divided, plus more
• package baby spinach, coarsely chopped
• cans white beans, rinsed
• unsalted butter
• " crusty Italian sub roll, cut in half crosswise, split lengthwise, or 2 ciabatt
• Parmesan or Pecorino, finely grated
• Chopped parsley